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Full-Text Articles in Animal Structures
Plasticity Of The Gnrh Neuronal System During Sexual Maturation Of The Male Djungarian Hamster, Kevin L. Buchanan
Plasticity Of The Gnrh Neuronal System During Sexual Maturation Of The Male Djungarian Hamster, Kevin L. Buchanan
Loma Linda University Electronic Theses, Dissertations & Projects
Onset of puberty in male Djungarian hamsters is characterized by increased pituitary gonadotropin secretion and testes maturation, and is controlled by neurons within the brain which secrete gonadotropin-releasing hormone (GnRH). Puberty is associated with increased numbers of morphologically unipolar, but not bipolar, GnRH neurons in the medial preoptic area (MPOA) and diagonal band of Broca (DBB). To test the hypothesis that delayed sexual maturation arrests this increase, males were exposed to short days or administered melatonin. Males with delayed puberty had significantly fewer unipolar GnRH neuron numbers in the MPOA and DBB comparable to pubertal controls in long days. Unipolar …
A Light And Electron Microscopic Study Of Visual Neurons In The Medulla Externa Of The Crab Hemigrapsus Nudus, Yu Cheng Liao
A Light And Electron Microscopic Study Of Visual Neurons In The Medulla Externa Of The Crab Hemigrapsus Nudus, Yu Cheng Liao
Loma Linda University Electronic Theses, Dissertations & Projects
The decapod crustacean with a relatively well-defined visual system have contributed significantly to our understanding of visual neuron morphology and physiology. The general morphology of the optic lobes of several decapods were initially described by Parker (1897) and Hanstrom (1924). In the past few years, several light and electron microscope studies have been made on the lamina ganglionaris: the first optic ganglion, of the lobster (Hamori and Horridge, 1966a); the crayfish (Hafner, 1974; Nassel, 1976a), and the crab (Stowe et al., 1977; Rafuse et al., in preparation). As yet, no adequate description has been made of the visual neurons in …