Dr. Maria J. Crespo

Dr. María J. Crespo


B.S. 1981ChemistryUniversity of Puerto Rico, Mayaguez, PR
M.S. 1987Analytical ChemistryUniversity of Puerto Rico, Mayaguez, PR
Ph.D. 1993PharmacologyUniv. of PR, School of Medicine, San Juan, PR
Postdoc 1995Vascular PhysiologyUniv. of PR, School of Medicine, San Juan, PR


My research goal is to understand the mechanisms underlying endothelial dysfunction and vascular alterations in hypertension, heart failure and diabetes.  The contribution of angiotensin II to the genesis of endothelial dysfunction is of particular interest.  The presence of a dysfunctional endothelium and alterations in the renin-angiotensin system have been postulated to be involved in the etiology of these complications. Precise mechanisms leading to these alterations, however, are still unknown. In addition, I have extensive experience in training and supervising under-represented minority (URM) students in research. These include undergraduate (over 40 students UPR-Biology), graduate, and post-graduate students (12 MD-students and 10 Postgraduate MDs). I have participated in a significant number of graduate Thesis committees of students from the Physiology Department, and from different departments of the School of Medicine and the University of Puerto Rico main campus.


My research interests are in the area of cardiovascular Physiology and Pharmacology, especially in pathophysiological conditions such as hypertension, diabetes and congestive heart failure. I am particularly interested in understanding the mechanisms underlying endothelial dysfunction and the vascular modifications present in these conditions. Alterations in the signal transduction pathway of nitric oxide (NO) and in the rennin-angiotensin system (RAS) are studied using animal models of hypertension, heart failure, and diabetes. The principal approaches used in my laboratory include aortic ring contractility studies, determination of cardiovascular variables (cardiac output, blood pressure, and heart rate), and evaluation of NO availability and RAS activity.  In addition, we are investigating new pharmacological approaches for the treatment of cerebral vasospasms, particularly in diabetes. For this purpose, we are investigating the effects of dantrolene, either alone or in combination with nimodipine, on blood flow velocity in the middle cerebral artery of a rat model of carotid artery-induced hemorrhagic vasospasms. We found that the combination of these drugs has synergistic effects that decrease vascular contraction, reduce lipid peroxidation, and improve vascular function in diabetic rats after the induction of cerebral vasospasms.  In summary, we are committed to the development of new adjuvant therapies designed to reduce cardiovascular complications, particularly in the diabetic population.


  • Román M, García L, Morales M, Crespo MJ. The combination of dantrolene and nimodipine effectively reduces 5-HT-induced vasospasms in diabetic rats. Sci Rep. 2021 May 10;11(1):9852. doi: 10.1038/s41598-021-89338-6. PMID: 33972638; PMCID: PMC8110522.
  • Román M, Ramírez JM, Morales M, Crespo MJ. Significant reduction of vascular reactivity with dantrolene and nimodipine in diabetic rats: a potential approach to cerebral vasospasm management in diabetes. Pharmacol Rep. 2020;72(1):126-134.
  • Crespo MJ, Roman M, Matias J, Morales M, Torres H, Quidgley J. Synergistic effects of Dantrolene and Nimodipine in Reducing PHE-induced Contraction and in Improving ACh-induced Relaxation in the Vasculature of Type-1 Diabetic Rats. Int J Endocrinol. vol. 2018, Article ID 9790303, 2018. doi:10.1155/2018/9790303.
  • Cruz N, Miranda JD, Crespo MJ. Modulation of Vascular ACE by Oxidative Stress in Young Syrian Cardiomyopathic Hamsters: Therapeutic Implications. J Clin Med. 2016 Jul 13;5(7). pii: E64. doi: 10.3390/jcm5070064.
  • González W, Altieri PI, Alvarado E, Banchs HL, Colón E, Escobales N, Crespo M. Celiac trunk and branches dissection due to energy drink consumption and heavy resistance exercise: case report and review of literature. Bol Asoc Med P R. 2015;107(1):38-40.
  • Altieri PI, Mundo J, Marcial JM, Banch H, Escobales N, Crespo M, Gonzalez W. Coronary Levels of Angiotensin II and Endothelin-1 in diabetic Patients with and without Coronary Artery Disease. J Bol Asoc Med P R. 2015;107(1):5-7.
  • Altieri PI, Marcial J, Banchs HL, Escobales N, Crespo M. The Metabolic Syndrome in Hispanics – The Role of Inflammation. Glob J Obes Diabetes Metab Syndr. 2015;2(1): 012-017.
  • Crespo MJ, Quidgley J. Simvastatin, atorvastatin, and pravastatin equally improve the hemodynamic status of diabetic rats. World Journal Diabetes. 2015;6(10):1168-78.
  • Hernández-Gil de Lamadrid J, Nieves-Rivera JJ, Mora L, Corretjer L, Altieri PI, Suárez A, Banchs HL, Muñiz J, Soto MI, Escobales N, Crespo M. Metabolic Changes After Roux-N-Y Bariatric Surgery In Hispanics. Bol Asoc Med P R. 2015 ;107(3):66-9. PubMed PMID: 26742199.
  • Crespo MJ, Cruz N, Quidgley J, Torres H, Hernández C, Casiano H, Rivera K,.  Daily Administration of Atorvastatin and Simvastatin for One Week Improves Cardiac Function in Type 1 Diabetic Rats Pharmacology. 2014;93(1-2):84-91.
  • Quidgley J, Cruz N, Crespo MJ. Atorvastatin Improves Systolic Dysfunction but Does Not Prevent the Development of Dilated Cardiomyopathy in Streptozotocin-induced Diabetic Rats. Therapeutic Advances in CV Disease 2014;8(4):133-144.
  • González W, Altieri PI, Banchs H, Iravedra D, Calderón R, , González- Cancel I, Gurrea  C, Nelson Escobales N and Crespo M. HDL as a Biomarker of Rejection in Heart Transplant. Glob J Obes Diabetes Metab Syndr 2014;1(1): 101-106.
  • Bou E, Hernandez P, Cerezo L, Altieri PI, Gurrea C, Figueroa R, Garcia P, Gonzalez-Cancel I, Defendini E, Escobales N, Crespo M, Banchs H. Heart tumors in Puerto Rico; De Novo Atrial Fibrillation as Clinical Presentation in a Subgroup of Patients.  P R Health Sci J. 2013;32(1):14-17.
  • Altieri PI, Marcial JM, Banchs H, Escobales N, Crespo M. Ethnicity and genetics are more important than diabetes mellitus and hypertension in producing cardiovascular events in patients with the metabolic syndrome: emphasis in the Puerto Rico population. Bol Asoc Med P R. 2013;105(3):56-63.
  • González W, Altieri PI, Alvarado S, Banchs HL, Escobales N, Crespo M, Borges W. Magnesium: the forgotten electrolyte. Bol Asoc Med P R. 2013;105(3):17-20.
  • Crespo MJ, Cangiano J, Altieri PI, Escobales N. Aliskiren Improves Left Ventricular Dysfunction and Reduces Cardiac Dilation in Syrian Cardiomyopathic Hamsters. J Cardiovasc Pharmacol  2012;59(6):547-542.
  • Crespo MJ,  Marrero M, Cruz N, Quidgley J, Creagh O, Torres H, Rivera K. Diabetes alters cardiovascular responses to anaesthetic induction agents in STZ-diabetic rats. Diab Vasc Dis Res. 2011;8(4):299-302.
  • Altieri PI, Figueroa Y, Banchs HL, de Lamadrid JH, Escobales N, Crespo M. Higher incidence of atrial fibrillation in the metabolic syndrome: a Hispanic population study. Bol Asoc Med P R. 2011 ;103(4):24-7.
  • Altieri PI, Figueroa Y, Banch H, Gil de Lamadrid J, Escobales N, Crespo MJ.  Metabolic Syndrome in a Hispanic Population-Cardiovascular Complications.” QScience Connect 2011;5 doi:10.5339/connect.2011.5.
  • Crespo MJ, Cruz N, Altieri PI, and Escobales N. Chronic Treatment with N-acetylcysteine (NAC) Improves Cardiac Function but Does Not Prevent Progression of Cardiomyopathy in Syrian Cardiomyopathic Hamsters.  J Cardiovasc Pharmacol Ther.  2011;16(2):197-204.
  • Marcial JM, Altieri PI, Banch H, Escobales N, Crespo M.  Metabolic Syndrome Among Puerto Ricans and other Hispanic Populations.  P R Health Sci J. 2011;30(3):145-151.
  • Escobales N,   Ramos JA, Santacana G,  Crespo MJ. Hemodynamic Alterations in the Coronary Circulation of Cardiomyopathic Hamsters: Age and Ang II-dependent mechanisms. J Card Fail. 2009;15(10):929-38.
  • Crespo MJ, Zalacain J, Dunbar D, Cruz N, and Arocho L. Cardiac Oxidative Stress is elevated at the Onset of Dilated Cardiomyopathy in STZ-diabetic Rats. J Cardiovasc Pharmacol Ther  2008;  13(1):64-71.
  • Crespo MJ, Cruz N, Altieri PI, Escobales N.  Enalapril and losartan are more effective than carvedilol in preventing dilated cardiomyopathy in the Syrian cardiomyopathic hamster. J Cardiovasc Pharmacol Ther.  2008;13(3):199-206.
  • Mundo_Sagardia JA, Figueroa Y, Altieri PI, Banch H, Escobales N, Crespo MJ. The atherosclerotic plaque.  P R Health Sci J. 2008;27(3):241-246.
  • Escobales N, Crespo MJ. Early pathophysiological alterations in experimental cardiomyopathy: The Syrian Cardiomyopathic Hamsters. P R Health Sci J. 2008;27(4):307-314.
  • Cruz N, Arocho L, Rosario L, Crespo MJ.  Chronic administration of Carvedilol improves cardiac function of 6-month-old Syrian cardiomyopathic hamsters. Pharmacology  2007;80:144-150.
  • Figueroa Y, Altieri PI, Banch H, Hernandez J, Lopez JC, Escobales N, Crespo M. Syncope in Puerto Rico.  Bol Asoc Med PR 2007;99(3):207-210.
  • Escobales N, Crespo MJ. Angiotensin II-dependent Vascular Alterations in Young Cardiomyopathic Hamsters: Role of Oxidative Stress. Vasc Pharmacol.  2006;44(1):22-28.
  • Crespo MJ, Quidgley J.  Statins decrease serotonin-induced contraction in coronary arteries of swine. Pharmacology  2006;76:141-147.
  • Crespo MJ, Altieri PI, Escobales N. Increased vascular angiotensin II binding capacity and ET-1 release in young cardiomyopathic hamsters. Vasc Pharmacol. 2006;44(4):247-252.
  • Crespo MJ, Quidgley J, Dunbar D. Differential Regulation of Left and Right Coronary Arteries of Swine. Pharmacology 2006;77:137-143.
  • Figueroa Y, Altieri PI, Banch H, Escobales N, Crespo M,  Defendini E, Gonzalez-Cancel I. Coronary Artery Abnormalities in Puerto Rico. P R Health Sci J. 2006;25(3):225-227.
  • Guerra J, De Jesus A, Santiago-Borrero P,  Roman-Franco A, Rodríguez E, Crespo MJ.  Plasma Nitric Oxide Levels Used as an Indicator of Doxorubicin-induced Cardiotoxicity.  Hematol J. 2005;5(7):584-8.
  • Escobales N, Crespo MJ. Oxidative-nitrosative Stress in Hypertension. Curr Vasc Pharmacol. 2005;3(3)231-246.
  • Altieri PI, Banch H, Escobales N, Crespo M, Rodriguez-Orengo J. The Role of Angiotensin Converting Enzyme-inhibitors and Angiotensin II Receptors Blockers in the Management of Arrhythmias and Atrial Fibrillation. Ital Heart J 2004;5(Suppl 1):39S-41S.
  • Altieri PI, Colon E, Rodriguez-Orengo J, Escobales N, Banch H, Crespo M, Figueroa Y. Quantitative analysis of the Vein Drainage to the Right atrium by Cardiovascular Magnetic Resonance in Patients with Chronic and Intermittent Atrial Fibrillation. Ital Heart J 2004;5(Suppl 1):124S-127S.
  • Crespo MJ, Moreta S, Gonzalez J. Cardiovascular Deterioration in STZ-diabetic Rats: Possible Role of Vascular RAS.   Pharmacology 2003;68(1)1-8.
  • Altieri PI, Escobales N, Rodriguez-Orengo J, Banch H, Crespo M. The Effect of Enalaprilat and Losartan in QT Dispersion. Clinical Cardiac Pacing and Electrophysiology. Monduzzi Editore 2003,  pp. 957-961.
  • Mundo-Sagardía J, Altieri P, Banch H, González R, Escobales N, Crespo M, Rodríguez-Orengo J, Cardona F, Torrado J. Role of Endothelin I and Angiotensin II in type 2 diabetics with coronary disease. Bol Asoc Med P R. 2003;95(5):45-50.
  • Mundo-Sagardía J, Altieri PI, Banch H, González R,  Escobales N, Crespo M,  Rodriguez-Orengo J, Cardona F, Torrado J. La relación entre los niveles coronarios de endotelina I y de angiotensina II y el diámetro de vasos coronarios en diabéticos tipo 2 con enfermedad coronaria. Rev. Lat. Cardiol. 2003;24(1):24-27
  • González-Pérez J, Crespo MJ. Acute Effects of Toremifene on the Vasculature of Intact and Menopause-induced Rats. Vasc Pharmacol 2003;40(4):205-211.
  • Crespo MJ, Dunbar DC. Enalapril Improves Vascular and Cardiac Function in STZ-diabetic Rats. Mol Cell Biol  2003;49(8) 1311-1318.
  • González-Pérez J, Crespo MJ. Chronic Effects of Selective Estrogen Receptor Modulator Toremifene on the Vasculature of Menopause-induced Rats. Vasc Pharmacol 2003:40(5):261-268.
  • Altieri PI, Escobales N, Rodriguez-Orengo J, Crespo-Bellido MJ, Banch H. El alcohol y las cardiomiopatías, mecanismos.  Rev Lat Cardiol 2002;23(2):66-67.
  • Altieri PI, Escobales N, Rodriguez-Orengo J, Crespo-Bellido MJ, Banch H. El papel del vino tinto en los síndromes coronarios agudos. Rev Lat Cardiol 2002;23(2):68-69.
  • Altieri-Nieto PI, Escobales-Alicea N, Rodríguez-Orengo JF, Banchs-Pieretti H, Crespo-Bellido MJ. The Effect of Angiotensin II Receptor Blockers and Converting Enzyme Inhibitors in QT Dispersion. Giornale Italiano di Aritmologia e Cardiostimolazione 2002; 5(S1):129-130.
  • Crespo MJ, WC de Mello. Chronic Administration of Losartan plus Hydrochlorothiazide Improves Vascular Status in Young Cardiomyopathic Hamsters. Eur J Pharmacol 2001;420 (2-3):133-141.
  • Crespo MJ. Interaction between AT-1 and Alpha-1 Adrenergic Receptors in Cardiomyopathic Hamsters. J  Cardiac Failure 2000;6(3):257-263.
  • Crespo MJ, Altieri PI, Escobales N.  Vastatins Compete with Norepinephrine for the Alpha-1 Receptor in Rat Aorta. Proceedings of the XXI Congress of European Society of Cardiology Monduzzi Editore, Italy-MediMond, USA, 1999. pp. 243-250.
  • Crespo MJ . Vascular Alterations  During the Development and Progression of Experimental Heart Failure.   J  Cardiac Failure 1999;5(1):55-63.
  • De Mello WC, Crespo MJ.   Correlation between Changes in Morphology, Electrical Properties, and Angiotensin converting Enzyme Activity in the Failing Heart. Eur J Pharmacol 1999;378(2):187 94.
  • Altieri PI, Crespo MJ, Escobales N, Rodriguez JF, Banch H.  The  antiarrhythmic properties of angiotensin converting enzyme inhibitors and angiotensin II blockers. G Ital Cardiol 1999;29(Suppl 5)442-444 .
  • Altieri PI, González R, Escobales N, Crespo MJ, Banch H.  Myocardial Remodeling in Hypertensive Patients. The Role of Converting Enzyme Inhibitions and Angiotensin II Receptor Blockers in Reducing Ventricular Arrhythmia. G Ital Cardiol 1998;28(1)353-356.
  • Altieri PI, González , Escobales N,  González R, Banch H,  Crespo MJ.  Lower Incidence of Coronary disease in Puerto Rico (USA Island) than in the Continental USA: a Possible Protective Effect of a Lower LDL/HDL Lipoprotein Ratio. Proceedings of the XIII World Congress of Cardiology Monduzzi Editore- 1998, pp. 13-16.
  • Crespo MJ, Escobales N, Altieri PI.  Altered Vascular Function in Early Stages of Heart Failure in Hamsters.  J  Cardiac Failure  1997;3 (4)311-318.
  • Altieri PI, González R, Escobales N, Crespo MJ, Banch H. Remodelado Miocardico y Vascular en los Pacientes Hipertensos. Papel de los Inhibidores de la Enzyma Convertidora y de los Bloqueadores de los Receptores de Angiotensina II. Rev Lat Cardiol 1997;18:55-60
  • Escobales N, Crespo MJ, Altieri PI, Furilla R.  Inhibition of Smooth Muscle Cell Calcium Mobilization and Aortic Ring Contraction by Lactone Vastatins.  J Hypertens 1996;14(1):115-121.
  • Crespo MJ, Escobales N, Rodriguez‑Sargent C. Endothelial Dysfunction in the San Juan Hypertensive Rat; Possible Role of Nitric Oxide Synthase.  J Cardiovasc Pharmacol. 1996;27(6) 802-808.
  • De Mello WC, Crespo MJ. Cardiac Refractoriness in the Rat Is Reduced by Angiotensin II.
  • J Cardiovasc Pharmacol 1995; 25(1):51‑56.
  • De Mello WC, Crespo MJ, Altieri PI. Effect of Enalapril on Intracellular Resistance and Conduction Velocity in Rat Ventricular Muscle. J Cardiovasc Pharmacol.  1993;22: 259‑263.
  • Altieri PI, De Mello W, Escobales N, Gonzales R, Crespo MJ. Enalapril in Congestive Heart Failure and Arrhythmias. New Trends in Arrhythmias 1992;7(4):1031‑1042.
  • De Mello WC, Crespo MJ, Altieri PI. Enalapril Increases Cardiac Refractoriness. J Cardiovasc  Pharmacol  1992;20:820‑825.
  • Vega CA, Crespo MJ.  Dissociation Constants of Primary Phosphate Ion for pH Control in 20 and 50 wt% 1‑propanol plus water solvents from 37 to 10 C.  J Chem Eng Data 1990; 35(4): 404‑406.


Departments of Physiology  and Anesthesiology
Associate Director, Hispanic Center of Excellence
University of Puerto Rico School of Medicine
Medical Sciences Campus, Office A-667
San Juan, PR, 00936-5067

Phone: (787) 758-2525 Ext. 5078