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With the exception of the agnathan fishes, a prolactin cell has been identified in all vertebrates in which it has been sought. This review examines the structure of the prolactin-producing pituitary cell in non-mammalian vertebrates, the manner in which it responds to natural and artificial stimuli, and its control by neural and humoral factors. Fundamental similarities and differences are described in an attempt to understand better its method of operation. Given our present state of knowledge, there is, among all the apparent diversity, a similarity in the basic structure and morphological response of this cell in teleosts, amphibians, reptiles, and birds. One can identify and speak with relative certainty about a specific adenohypophysial cell called a “prolactin cell.” More profound differences may be found at the level of control mechanisms, chemistry of the hormone(s), and the nature of receptivity and response of target tissues. It appears that although there are basic similarities in the design of the prolactin cell, the systems that control its activities may differ and the similar products produced by the cell may be used toward different ends. [ABSTRACT FROM PUBLISHER]

Presents several news briefs related to the field of bioscience. Prize awarded to John B. Gurdon of the University of Cambridge in England; Amount of grant awarded to Stephen Safe, a distinguished professor at the Veterinary Physiology and Pharmacology Department of the College of Veterinary Medicine at Texas A&M University; Acreage of the Oak Ridge National Environmental Research Park, which has been designated as a unit of the Southern Appalachian Biosphere Reserve; Amount of budget request made by the United States Department of Agriculture for the establishment of a Biological Control Service Institute; Biography of Russell Aiuto, who was named director of the Division of Teacher Preparation and Enhancement at the National Science Foundation; Members that were appointed to the U.S. National Committee for the International Union for Biological Sciences; Award given to Richard H. Pough for his work in land preservation and animal protection; Opportunities; Courses; Publishing news.

The current state of our knowledge of the morphology and histo- and cytophysiology of the teleost pituitary gland is presented. The zonation that characterizes the adenohypophysis is based on the regional distribution of specific cell types. As a result there is also a functional zonation indicated by specific hormones emanating from clearly identifiable parts of the gland. These observations make the teleost hypophysis ideal for the study of problems that may be basic to all vertebrates. The ultrastructure of hypophysial cells is presented and related to observations at the light microscope level. The manner in which secretory granules are released from specific cells is compared, and the problem of evaluating “cell activity” discussed. The application of immunohistochemical techniques to the study of the teleost pituitary gland is reviewed, and its use as a tool of investigation for future studies evaluated. These methods have helped to elucidate the cellular source of teleost pituitary hormones and have confirmed the findings of the histophysiologists. [ABSTRACT FROM PUBLISHER]

Features the International Union of Biological Sciences (IUBS) and its United States National Committee (USNC). Existing scientific programs of the USNC; Diversitas program; Themes of research programs; Contact information.