Dr. Annabell Segarra from UPR-Medical Sciences Campus


Does the “Night-­float rotation” alter sleep/wake cycles and circadian rhythms of UPR physician residents: Modulation by chronotypes.

Co-PI: Yohana De Jesus, MD
Co-PI: José Agosto, PhD

The research in our laboratory focuses on the neurochemical substrates that participate in mediating sex differences in motivated behaviors. For the last 30years, our laboratory has studied the mechanisms by which sex steroids modulate the response to drugs of abuse, such as cocaine and opioids. Our studies use a whole system approach, measuring locomotor activity, sensitization, and conditioned place preference in response to drugs. To investigate the signal transduction mechanisms involved, we use autoradiography, confocal microscopy, immunohistochemistry, Golgi, and Western blots. We also use RIA and ELISA to measure plasma levels of hormones. With financial assistance from the DOD and RCMI, I established a core facility for image analysis 25years ago, enlarged it to include confocal microscopy, and continue to direct and secure funds for this facility. I have also served as thesis advisor to 2 MS and 6PhD students,1 MARC undergraduate, trained 2 postdoctoral fellows, 157 undergraduates, and served on more than 40thesis committees. I am currently an advisor of 2 PhD students and have 3 undergraduate students in my laboratory.