From metabolism and behavior to respiratory physiology: an educational and research perspective.

Throughout my academic career, I have been extremely fortunate to have as mentors, teachers, and advisors, remarkable individuals who helped me develop into a competent researcher and passionate teacher. This essay describes a period in my career as a graduate student that was challenging, but also rewarding. I was fortunate to have contact with world-class researchers and teachers, including Drs. Clyde Herried, Leon Fahri, Hermann Rahn, Donald Riggs, Verner Noell, and Barbara Howell. In addition, I attended excellent University of Buffalo Department of Physiology seminars presented by world-renown scientists. Looking back on the experience, allows me to appreciate the large impact they made on my subsequent career in education and research in physiology and neurobiology.

Effects of thyroidectomy, T4, and DITPA replacement on brain blood vessel density in adult rats.

In hypothyroid patients, altered microvascular structure and function may affect mood and cognitive function. We hypothesized that adult male hypothyroid rats will have significantly lower forebrain blood vessel densities (BVD) than euthyroid rats and that treatment with 3,5-diiothyroprionic acid (DITPA) (a thyroid hormone analog) or thyroxine (T(4)) will normalize BVDs. The euthyroid group received no thyroidectomy or treatment. The other three groups received thyroidectomies and pellets. The hypothyroid group received a placebo pellet, the DITPA group received an 80-mg DITPA-containing pellet, and the T(4) group received a 5.2-mg T(4) slow-release pellet for 6 wk. Body weights, cardiac function, and body temperatures were measured. A monoclonal antiplatelet endothelial cell adhesion antibody was used to visualize blood vessels. The euthyroid group averaged body weights of 548 +/- 54 g, while the hypothyroid group averaged a body weight of 332 +/- 19 g (P value < 0.001). Relative to the euthyroid group, the DITPA-treated group was significantly lighter (P value < 0.05), while the T(4)-treated group was comparable in body weight to the euthyroid group. The same trends were seen with body temperature and cardiac function with the largest difference between the euthyroid and hypothyroid groups. BVD in the euthyroid group was 147 +/- 12 blood vessels/mm(2) and in hypothyroid group 69 +/- 5 blood vessels/mm(2) (P = 0.013) but similar among the euthyroid, DITPA, and T(4) groups. These results show that hypothyroidism decreased BVD in adult rat forebrain regions. Moreover, DITPA and T(4) were efficacious in preventing effects of hypothyroidism on cardiac function and BVD.