The Sexual Cycle

Serotonin and melatonin are evidently involved in maintenance of the 24-h circadian rhythm of the body (see Section 13).792/792a Melatonin regulates the sexual cycle in photoperiodic animals and influences the onset of puberty.792-794 The serotonin content of the brain is influenced by the diet, being higher after a meal rich in carbohydrates. Serotonin may serve as a chemical message sent from one set of neurons to the rest of the brain, reporting on the nature of dietary intake.784 Melatonin, which can readily form free radicals, may function as part of the body s antioxidant system.795 796... 

The sexual cycle (sporogony) takes place in the female anopheline mosquito, while the asexual cycle (schizogony) takes place in humans. 

The cyclic variation in vaginal drug permeability observed in rhesus monkeys in association with the rhythmic pattern of the sexual cycle suggests that the vaginal absorption data generated in the rhesus monkeys may be more reflective of what will occur in humans. The rhesus monkey is, therefore, a good animal model for the research and development of intravaginal delivery devices. 

The responses of uterine muscle to Epi vary with phase of the sexual cycle, state of gestation, and dose. During the last month of pregnancy and at parturition, Epi inhibits uterine tone and contractions. fi -Selective agonists (e.g., ritodrine or terbutaline) can delay premature labor, although... 

Kurmukov AG, Akhmedkhodzhaeva KhS (1975) The experimental influence of psoralen and rnfekundin on the sexual cycle and embryogenesis. Meditsinskii Zh Uzbekistana (8) 35 (in Russiem) Kurmukov AG, Akhmedkhodzhaeva KhS (1994) Estrogennuiye lekarstvennuiye preparatui iz rastenii roda Ferula (Estrogenic medicinal preparations of plants in the Genus Ferula). Ibn Sino, Tashkent (in Russian)... 

Cyt b6/f complexes are withdrawn from the thylakoid membranes in gametes. This process is under a dual mitochondrial and chloroplast control, most likely through the intracellular ATP level. The inactivation of photosynthesis at the cyt b6/f level further contributes to a limitation in ATP synthesis in the gametes. Thus low ATP levels may be required at some stages of the sexual cycle in C. reinhardtii. 

Ecdysone has proved to be active in all the orders of insects investigated. Of major interest is the influence on symbionts in certain cockroaches. The symbionts go through a sexual cycle while the host casts its skin. The sexual cycles can be induced by means of ecdysone without the host undergoing ecdysis . 

In our lab recently the construction of a (preliminary) genetic map was achieved by analysing the progeny of a cross between two fungicide/antibiotic resistant strains by molecular methods (see below). Therefore the sexual cycle and meiotic recombination could form a valuable basis for molecular genetic approaches, inspite of the pitfalls and technical problems of the system. 

Raju, N.B. 1992. Genetic control of the sexual cycle in Neurospora. Mycol. Res. 96 241-262. 

Jaenicke, L. and Boland, W. (1982) Signal substances and their reception in the sexual cycle of marine brown algae. Angew. Chem. Int. Ed.. 21, 643-653. 

Results from the sexual cycle where basal bodies disappear in the... 

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