In various species of fishes, the importance of visual cues in the determination of environmental threat and subsequent predator avoidance is clear. Chemical cues also play an essential role facilitating predator avoidance. Among fish in the superorder Ostariophysi, club cells in the epidermis produce an alarm substance.
View Article and Find Full Text PDFThe estrogen receptor-alpha (ERalpha) pituitary-specific variant, TERP-1, is regulated dramatically by physiological status. We examined hormonal regulation of the TERP-1 promoter in transient transfection assays in GH3 somatolactotrope cells. We found that 17beta-estradiol (E2), genistein, androgen, pituitary adenylate cyclase-activating peptide, and forskolin (FSK) all stimulated TERP-1 promoter activity, whereas progesterone had no effect.
View Article and Find Full Text PDFThe purpose of these studies was to examine possible mechanisms of Orphanin FQ/Nociceptin (OFQ/N)-induced prolactin release. We investigated the involvement of the dopaminergic neurons by quantifying DOPAC:DA levels in the median eminence and neurointermediate lobe following central administration of OFQ/N to female Sprague-Dawley rats. To specifically determine the involvement of the tuberoinfundibular dopaminergic neurons, immunocytochemical studies were conducted to visualize c-fos protein expression in the arcuate nucleus following central administration of OFQ/N.
View Article and Find Full Text PDFEstrogen receptor (ER)alpha is a ligand-inducible transcription factor that mediates the physiological effects of 17beta-estradiol (E2). In the uterus, E2 is involved in tissue growth, maintenance, and differentiation. Delta5ERalpha (Delta5) is an ERalpha variant protein expressed in uterine tumors but not in normal tissue.
View Article and Find Full Text PDFThe specificity of the orphaninFQ (OFQ)/nociceptin (N)-induced prolactin increase was determined in male and female rats by pretreating animals with different doses of [Phe(1)Psi(CH(2)-NH)Gly(2)]NC(1-13)NH(2), a compound originally reported to be a specific OFQ/N antagonist. In addition, the effect of naloxone pretreatment on OFQ/N-induced prolactin release was examined to determine if OFQ/N's effects were mediated by opiate receptors. Furthermore, dose response studies using [Phe(1)Psi(CH(2)-NH)Gly(2)]NC(1-13)NH(2) only were performed to determine potential agonist activity of this drug.
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