Dr. Raphael J. Witorsch
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Contact Information
Virginia Commonwealth University P.O. Box 980551 Richmond, Virginia 23298-0551 Tel: 804-828-4486 Fax: 804-828-7382 email: witorsch@vcu.edu |
Raphael J. Witorsch received his A.B. in biology in 1963 from New York University and completed his graduate studies in physiology at Yale University (M.S. 1965, Ph.D. 1968), Dr. Witorsch spent two years in postdoctoral training at the University of Virginia before joining VCU in 1970.
Teaching
I have been Director of the Mammalian Physiology Course for Dentistry and Pharmacy Students (Spring semester) since 2001. This course is taught simultaneously to approximately 90 Dental Students and 130 Pharmacy students. Since the enrollment in the course is unusually large, a live lecture is conducted in the School of Medicine (attended mainly by Pharmacy students) and a simultaneous video feed is sent over to the Dental School. In this course I lecture on selected topics of endocrine physiology (adrenal cortex and reproduction). I also lecture annually in the M1 Physiology course (Spring semester) on the following topics: hypothalamus and posterior pituitary, adrenal cortex, male reproduction, female reproduction, and pregnancy and lactation. Throughout my academic career I have trained numerous MS, PhD, and post-doctoral students. At the present time, no training opportunities are offered in my laboratory.
Research
Throughout my 40 year academic career I have conducted research and published in the following areas: neuroendocrinology (hypothalamo-pituitary-adrenocortical axis), steroidogenesis, prostate physiology, prolactin actions and mechanisms of action, prolactin-glucocorticoid interactions in target cells, and most recently endocrine and reproductive toxicology. The possibility that environmental chemicals might mimic or antagonize the action of glucocorticoids has been a neglected but potentially important issue in the emerging field of endocrine disruption. I have developed a "G-screen" assay using a rat lymphoma cell line that responds specifically to glucocorticoids (such as dexamethasone, cortisol, corticosterone) with apoptosis (representative of stress-induced immunosuppression, a physiological response). The assay is used to screen environmental chemicals for their ability to mimic or antagonize glucocorticoid action. I have tested about 50 environmental chemicals suspected of having endocrine disruptive effects and have some very interesting, novel, and potentially important observations with regard to general toxicity, mixtures, and modulation of a cell’s response to glucocorticoids. Over the last few years I have published several review articles on such topics as environmental estrogen mechanisms, the physiological and toxicological significance of effects of the plastics-additive, bisphenol A, and the role of stress and adrenal steroids on mammalian reproduction.
Selected Publications
Books:
Hubbard, J.R., M.Y. Kalimi, R.J. Witorsch: Review of Endocrinology and Reproduction, Renaissance Press, Richmond, 1988.
Witorsch, R.J. (ed.): Reproductive Toxicology, Second Edition. Target Organ Toxicology Series, Hayes A.W., Thomas, J.A., and Gardner, D.E., Eds., Raven Press New York, 1995.
Recent Articles and Abstracts:
Witorsch, R.J. Low-dose in utero effects of xenoestrogens in mice and their relevance to humans: an analytical review of the literature. Food and Chemical Toxicology 40: 905-912, 2002. PubMed
Witorsch, R.J. Endocrine disruptors: can biological effects and environmental risks be predicted? Regulatory Toxicology and Pharmacology 36: 118-130., 2002. PubMed
Borgert, C,J,, Lakind J.S., and Witorsch R.J.: A critical review of methods for comparing estrogenic activity of endogenous and exogenous chemicals in human milk and infant formula. Environmental Health Perspectives.111: 1020-1036, 2003. PubMed
Cooke, PS, Holsberger DR, Witorsch RJ, Sylvester PW, Meredith JM, Treinen KA, and Chapin RE, Thyroid hormone, glucocorticoids, and prolactin at the nexus of physiology, reproduction, and toxicology. Toxicology and Applied Pharmacology.194: 309-335, 2004. PubMed
R. J. Witorsch, J.K. Taylor, C.S. Jones: Microassay for the detection of glucocorticoid agonist/antagonist activity in environmental chemicals. (45th Annual Meeting of the Society of Toxicology). The Toxicologist Supplement to Toxicological Sciences: 90: 399, 2006 (Abstract).
Goodman, J.E., E.E. McConnell, I.G. Sipes, R.J. Witorsch, T.M. Slayton, C.J. Yu, A.S. Lewis, L.R. Rhomberg: An updated weight of the evidence evaluation of reproductive and developmental effects of low doses of bisphenol A. Critical Reviews in Toxicology. 36: 387-457, 2006. PubMed