Publications by authors named "Lepak K"

The PFC, through its high degree of interconnectivity with cortical and subcortical brain areas, mediates cognitive and emotional processes in support of adaptive behaviors. This includes the formation of fear memories when the anticipation of threat demands learning about temporal or contextual cues, as in trace fear conditioning. In this variant of fear learning, the association of a cue and shock across an empty trace interval of several seconds requires sustained cue-elicited firing in the prelimbic cortex (PL).

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The purpose of this study was to determine if toxic effects of cobalt on the murine testis could be prevented by zinc, an essential metal for spermatogenesis. CD-1 male mice were administered one of the following in their drinking water: 1) 400 ppm CoCl2, 2) 800 ppm ZnCl2, 3) 400 ppm CoCl2 + 800 ppm ZnCl2, or 4) distilled water. After 13 weeks, animals were sacrificed and testes were excised, weighed, and processed for histologic study.

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The effects of SQ 29,548 on vasoconstrictor responses were investigated in the feline mesenteric vascular bed. Injections of the thromboxane (TX) A2 mimics, U46619 and U44069, caused dose-related increases in mesenteric arterial perfusion pressure. After administration of SQ 29,548, 0.

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Human alpha-calcitonin gene-related peptide (CGRP) is a substance immunohistochemically present in a number of organ systems; however, the biologic significance of this peptide is uncertain. The present study was undertaken to investigate the effects of CGRP in the feline mesenteric vascular bed under conditions of controlled blood flow. Bolus injections of CGRP decreased mesenteric perfusion pressure in a dose-related fashion.

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