I am happy to participate in this academic celebration of the 30 years of the Tlaxcala Center for Behavioral Biology (CTBC). Since before its founding, through the international exchange program that Carlos Beyer and I started through our universities, I became a close friend and colleague with the CTBC founding members when they were impressive students of the first generation of the Master's Degree in Reproductive Biology at CIRA. It was the late 1980's and early 1990's when we collaborated on research projects in my laboratory at the Institute of Animal Behavior at Rutgers University (NJ, USA).

Then we participated frequently in the annual Conference on Reproductive Behavior, one of which Carlos and I organized in Tlaxcala, and at the Society for Neuroscience Conference in various cities in the USA. Although the years have passed, our friendship and active research collaborations have continued. For example, in one of our collaborative projects with Pablo Pacheco, Margarita Martínez, Beverly Whipple and others, we found that women from Tlaxcala and Veracruz who reported that they ate hot chili peppers daily since their early childhood, had less pain blockage from vaginal self-stimulation than women who ate chili peppers only rarely. This was evidence that a particular type of (c-)nerve fibers that carry vaginal sensation may have been damaged by their continual daily pepper consumption.

I felt honored to be invited by Yolanda Cruz 4 years ago to participate in the tribute to Pablo Pacheco in the context of an international course on the pathophysiology of the pelvic area organized in Tlaxcala. At the CTBC there are lines of anatomical and behavioral research on female and male physiology of the genitourinary organs and on the related striated pelvic and perineal musculature. One such example is the role of ejaculatory phenotypes and copulatory analgesia that Rosa Angélica and one of her students analyzed. I greatly appreciated Rosa Angélica invitation to participate, on the basis of my studies on female copulatory analgesia. Knowing that male rats, like men, have copulatory phenotypes (fast, intermediate, and slow ejaculators), we found that the faster the males copulated, the more insensitive they became to pain.

In conclusion, I must emphasize how impressed and proud I am that every one of the students who participated in our Mexico-USA exchange program by collaborating in research in my laboratory at the Institute of Animal Behavior has developed into an established researcher with their own lines of research. It is a truly great pleasure and honor for me to continue our long-lasting friendship and collaboration.