Reproduction, prostaglandins

Park, B., ]. M. McPartland, and M. Glass. Cannabis, cannabinoids and reproduction. Prostaglandins Leukot Essent Fatty Acids 2004 70(2) 189-197. 

Poyser, N. (1981) Prostaglandins in Reproduction. Prostaglandin Research Studies Series, Vol. 2, pp. 1-272, John Wiley and Sons, England. 

Rats fed a purified nonlipid diet containing vitamins A and D exhibit a reduced growth rate and reproductive deficiency which may be cured by the addition of linoleic, a-linolenic, and arachidonic acids to the diet. These fatty acids are found in high concentrations in vegetable oils (Table 14-2) and in small amounts in animal carcasses. These essential fatty acids are required for prostaglandin, thromboxane, leukotriene, and lipoxin formation (see below), and they also have various other functions which are less well defined. Essential fatty acids are found in the stmctural lipids of the cell, often in the 2 position of phospholipids, and are concerned with the structural integrity of the mitochondrial membrane. 

Rodriguez, C. M., et al. (2000). Expression of the lipocalin-type prostaglandin D synthase gene in the reproductive tracts of Holstein bulls. J. Reprod. Pert. 120, 303-9. 

Tokugawa, Y., et al. (1998). Lipocalin-type prostaglandin D synthase in human male reproductive organs and seminal plasma. Biol Reprod. 58, 600-7. 

Recently, a novel class of prostaglandin derivatives, PG-1,15-lactones (Fig. 1) of both E [16] and F [17] series, has been reported to occur in the opisthobranch mollusc Tethys fimbria, along with smaller amounts of some of the corresponding PGs. Some lactones were present mainly in the mucous secretion and dorsal appendages known as cerata, while others were more abundant in the mantle. Fatty acid esters of PGF-1,15-lactones (C9 and Cu) were found only in T. fimbria eggmasses and reproductive glands (ovotestis). The structural variety of the lactones and the data on their distribution in the body... 

Fatty messengers Fatty messengers are discussed in Chapter 11. Those involved in sexual reproduction are the eicosanoids. The prostaglandins that are involved in reproduction are particularly PGE2 and PGFaa. 

In fish reproduction, the best-investigated pheromone system is that of the goldfish [Carassius auratus). Here, sex steroids and prostaglandins play important roles. The female produces two pheromones sequentially a preovulatory primer pheromone and a postovulatory prostaglandin pheromone that act on the male. 

ChaUis JR et al. Prostaglandins and mechanisms of preterm birth. Reproduction 2002 81 633-641. 

The actions of prostaglandins on reproductive smooth muscle are discussed below under section D, Reproductive Organs. PLATELETS... 

Studies with knockout mice have confirmed a role for prostaglandins in reproduction and parturition. COX-l-derived PGF2K appears important for luteolysis, consistent with delayed parturition in COX-l-deficient mice. A complex interplay between PGF2E and oxytocin is critical to the onset of labor. EP2 receptor-deficient mice demonstrate a preimplantation defect, which underlies some of the breeding difficulties seen in COX-2 knockouts. 

Kirton KT, Kimball FA, Porteus SE. Reproductive physiology prostaglandin-associated events. Adv... 

Sales KJ, Jabbour HN. Cyclooxygenase enzymes and prostaglandins in pathology of the endometrium. Reproduction. 2003 126 559-567. 

Reproductive smooth muscles Prostaglandins Ej, E2, and F cause contraction of the pregnant and nonpregnant human uterus, and produce laborlike contractions. In contrast to oxytocin, this effect is possible in all stages of pregnancy. 

The prostaglandins and thromboxanes have major effects on four types of smooth muscle airway, gastrointestinal, reproductive, and vascular. Other important targets include platelets and monocytes, kidneys, the central nervous system, autonomic presynaptic nerve terminals, sensory nerve endings, endocrine organs, adipose tissue, and the eye (the effects on the eye may involve smooth muscle). 

The physiologic role of prostaglandins in reproduction has been intensively studied since the discovery of prostaglandins in the seminal plasma of primates and sheep. It has been suggested that... 

Di Marzo, V., Minardi, C., Vardaro, R. R., Mollo, E., and Cimino, G., Prostaglandin F-l, 15-lactone fatty acyl esters a prostaglandin lactone pathway branch developed during the reproduction and early larval stages of amarine mollusc, Comp. Biochem. Physiol., 101B, 99, 1992. 

Reproductive behavior in fish is a phenomenon that is synchronized by chemical means.138-140 A fraction of the steroids that are involved in the internal development of oocytes are released by females into the environment, where they are encountered by males — detection of this steroid induces internal hormonal changes in males that bring about enhanced sperm production. At a later time in the reproductive cycle, prostaglandins in the female that are associated with the follicular rupture of mature egg cells are released. Upon detection of the appropriate prostaglandin, males begin mating behaviors that culminate in the release of gametes by both sexes. 

Prostaglandins are fatty acid derivatives that are even more powerful biochemical regulators than steroids. They are called prostaglandins because they were first isolated from secretions of the prostate gland. They were later found to be present in all body tissues and fluids, usually in minute quantities. Prostaglandins affect many body systems, including the nervous system, smooth muscle, blood, and the reproductive system. They play important roles in regulating such diverse functions as blood... 

The gorgonian coral Plexaura homomalla is a source of prostaglandin A2. This compound can be converted to medically useful prostaglandins that regulate mammalian reproduction, blood pressure, and digestion. 

The prostaglandins occur in all tissues but in very small amounts. They act on loci in the same cells as those in which they are synthesized, and their biological roles are diverse e.g., they function in the female reproductive system during ovulation, menstruation, pregnancy, and parturition, and they stimulate uterine muscle contraction. 

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