Sexual mounting

Infected individuals who never mount an immune response. Since the immune response varies from person to person, a few infected individuals do not produce antibodies to HIV. These are rare but documented cases of individuals who remain antibody negative but spread HIV infection to their sexual partners. 

In rodents the most commonly studied female sexual behavior is the lordosis posture, in which the female remains immobile and concavely arches her back. Lordosis, usually in response to mounting, has been used as an index of female sexual receptivity. In addition, a variety of other measures such as elective proximity to a male have been used to index sexual proceptivity. Studies of these and related behaviors have shown that in rats ovarian secretions are essential for the expression of lordosis and can increase the expression of a variety of sociosexual behaviors (Pfaff, et al., 1994). Surgical removal of the ovary (ovariectomy) eliminates female sexual behavior in most rodents, and treatments with estrogen and progesterone can produce levels of sexual receptivity that closely resemble those seen in a gonadally-intact estrous female. 

Mesocricetus auratus M Sexually native mounting Sexual behavior Meredith, 1986... 

Development of sexual behavior can be affected by neonatal pharmacological treatment with the monoamine oxidase inhibitor pargyline, the monoamine depletor reserpine as well as with the acetylcholine esterase inhibitor pyridostigmine. These results suggest that biogenic amines are involved in sexual differentiation of the brain (refs. 162, 163). Pargyline treatment from day 1 to 14 or day 15 to 28 resulted in earlier development of puberty in female rats and delayed appearance of puberty in male rats. Male sexual behavior was decreased in both sexes. Treatment with reserpine on days 1, 4, 7 and 10 delayed the manifestation of puberty in both sexes, and caused disturbed female ovarian cycles and decreased male mounting behavior. 

Because most standard animal reproduction studies do not observe mating, they do not contain evaluations of an agent s effect on sexual behavior. If a study does report observations of mating, the failure of female rodents to assume a lordotic position and to accept mounting is evidence of abnormal sexual behavior. Additional signs include running from or fighting with the male (Uphouse and Williams 1989 Uphouse 1985). 

Classification of the groups according to sexual performance before treatment Number of animals Total number of mountings (M) intromissions (I) and ejaculations of the groups during treatment M I E ... 

In the (-)-deprenyl-treated group the total number of mountings and intromissions increased tremendously and ejaculations were also displayed. Thus due to the enhancer effect of (-)-deprenyl the excitability of the mesencephalic dopaminergic neurons was increased and the efficiency of sexual performance of the rats changed accordingly. 

Chronic dietary restriction of tryptophan has been reported to be associated with clear-cut changes in behavior, including increased sexual performance (mounting behavior) in male rats and rabbits,89 90 presumably by attenuating serotonergic function. 

Antiracist politics is challenged to devise responses to the obsessive structure of racialization if it is to mount a more effective intervention in the post-civil rights era. Liberal models of multicultural unity-in-diversity and conservative prescriptions for colorblindness have proved themselves to be as damaging to movements for radical social change as they are intractable as elements of contemporary political discourse (West 1994). Critics on the Left seem unsatisfied with the bleakness of these options yet at a loss for an alternative analytic framework. This is especially true with regard to matters of interracial sexuality ... 

Aphrodite, the n5miph-goddess of midsummer, would destroy the sacred king by tearing out his sexual organs just as the queen-bee destroys the drone.Her Priestesses displayed a golden honeycomb at her shrine on Mount Eryx. 

Paralleling the findings for crabs, Stebbing et al. (2003) demonstrated that sexually mature female crayfish, Pacifastacus leniusculus, released a pheromone that stimulated mating behavior in males. If water conditioned by mature females was passed through an air-stone into containers holding males, these males commonly seized, mounted, and in a few cases deposited spermatophores onto the air-stones. Such behaviors did not occur if the air-stones carried water conditioned by immature females or control water that had not held crayfish (see also Chap. 13). 

Most injection studies have been performed in projection areas of the serotonergic system and in the raph nuclei from which serotonergic fibers emanate. HiUegaart et al. [42] reported that 8-OH-DPAT ii jected into the nucleus accumbens produced a facilitation of the male rat sexual behavioiir, as evidenced by a decrease in number of mounts and intromissions to ejaculation, as well as by a decrease in the postejaculatory interval. Injections into the olfactory tubercle had no effects on sexual behaviour. Femdndez-Guasti et al. [43] confirmed the stimulatory effects of 8-OH-DPAT after local application into the nuclear accumbens, but edso found similar effects for medial preoptic area injections. They foimd no effects after dorsal raph4 administration, in line with HiUegaart et al. 

Mount and Stephan 145) reported a similar investigation in which tests with the fathead minnow were conducted at a water hardness of 31 mg/liter as CaCOa. Copper at 18.4 /xg/liter produced about 50% mortality, retarded growth and sexual development of survivors, and prevented spawning. In addition, larvae from unexposed parents suffered complete mortality when treated at this concentration. Chronic exposure at 10.6 / g Cu/liter produced no observable effects on adults and did not inhibit reproduction. Comparing these results with the earlier study by Mount 142), it may be assumed that growth and reproduction of the fathead minnow are somewhat more affected when copper is administered in soft water. 

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