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At least 19 recordsLinked to original sources

PubMed1977

Secretion in the rat coagulating gland (anterior prostate) after copulation.

The effect of copulation on the rat coagulating gland (anterior prostate) was studied. At 4 to 6 h after the beginning of copulation the coagulating glands of rats that had produced copulatory plugs were nearly empty of secretion. Ultrastructurally, the coagulating gland has large cisternae of rough endoplasmic reticulum (RER) and few condensing vacuoles or secretion granules. After copulation the number of secretion granules and the frequency of their expulsion into the lumen increased. Also in the lumen were "fragmentation" vesicles (50-100 nm diameter) that were bounded by a unit membrane and appeared to arise from microvilli. At 4, 6, and 7h after the beginning of copulation there was an increase in apical blebbing. Blebbing was found in both perfusion and immersion-fixed tissue. Also, after copulation there was an increase in "light cells" that were characterized by reduced RER cisternae, an electron lucent cytoplasm, and atrophic Golgi apparatus. The luminal ground substance, secretion granules, and some Golgi elements, contained polysaccharides as seen with the periodic acid-thiocarbohydrazide-silver proteinate method.

Animals↗

PubMedDate not supplied

Red cell and total blood volumes during sexual excitement and copulation in the boar.

Measurements of hematocrit, total plasma protein and red cell volume were made during sexual excitement and copulation in boars. Red cell volume (RCV) was determined by isotope dilution technique using endogenous 51Cr-tagged red cells. Basing on these data changes in the total blood volume (TBV) and plasma volume (PV) were calculated by 2 indirect methods. RCV increased by 12% to 16% in the intial phase of ejaculation and remained increased during ejaculation and 40 minutes after copulation. TBV and PV decreased during copulation, greatest drop being found in the final phase of ejaculation. After ejaculation the TBV was increasing, first to the resting value before copulation (about 20 minutes after copulation), thereafter it became markedly higher than during the resting period. Depending on the method used for calculation significant differences were found in the quantity of TBV and PV drop during ejaculation.

Animals↗

PubMed1979

Copulation and intermale aggression in rats.

Attack behavior of reliably aggressive male Long-Evans rats against unfamiliar male intruders was observed immediately following copulation to one or more ejaculations. Compulatory series to five ejaculations did not differ from copulation to a single ejaculation or from a noncopulatory control in affecting aggressive behavior. Repetitive biting attacks occurred in all conditions, with comparable wounding. Evidently, the male postejaculatory state of insensitivity to sexual stimuli does not extend to stimuli eliciting intermale aggression. A second experiment determined the attack-eliciting capacity of foreign males placed in the home cage of an actively copulating male. As intromissions increased and the interval to ejaculation decreased, the probability of intermale aggression and interruption of copulation diminished. The results are discussed in reference to sexual and aggressive strategies of the copulating male.

Aggression↗

PubMed1975

Investigation of genetic factors influencing duration of copulation in "eastern" and "western" Drosophila athabasca.

Observations of mating behaviour were made on "eastern" and "western" Drosophila athabasca and on flies of mixed genetic background. Duration of copulation in mixed combinations of D. athabasca is determined by the male. In F1 males the source of X-chromosome, whether eastern or western, partly determined suration of copulation. However, durations of copulation of backcross males suggest autosomal influence, in that males derived from an eastern backcross demonstrate significantly shorter durations than males derived from a western backcross. In addition, durations of copulation from F2 combinations exhibit greater variance than the F1 and thereby represent evidence of F2 segregation.

Animals↗

PubMed1976

Copulation in noncopulators: effect of PCPA in male rats.

Twenty eight virgin male rats who failed to mount spontaneously on four successive mating tests were randomly assigned to two equal groups. One group received four daily injections of PCPA (100 mg/kg-IP), and the other, four vehicle injections. About 24 hr after the last injection all rats were subjected to a mating test. Eight rats of the PCPA group and only two of the vehicle, started to copulate. The difference is significant at the 0.05 level (two-tail). The 18 rats that did not start to copulate, failed to do so also on a repeated test a week later, and were then given four additional daily injections of PCPA. Sixteen of them started to copulate on the following mating test. Most of the rats copulated successfully on additional mating tests that took place three to eight weeks later, in the absence of further PCPA treatment.

Animals↗

PubMed1978

Interaction between penile reflexes and copulation in male rats.

Intact, unanesthetized male rats were place in a supine position, with the penile sheath continuously retracted. Three forms of penile reflex were displayed: erections, cups, and flips. The reciprocal relation between copulation and the penile reflexes occurring in supine tests was explored in four experiments. In Experiment 1, sexual exhaustion depressed all penile reflexes, but the reflexes returned to baseline levels within 8 hr, long before copulatory potential. In Experiment 2, reflexes were depressed to exhaustion levels after fewer ejaculations than were required for sexual exhaustion, an indication that reflexes are more readily evoked during copulation than in supine tests. Experiment 3 determined that a rat's penile-reflex potential may be enhanced by placing the rat in a copulation-test cage, by allowing the male a few antecedent intromissions, or by allowing an antecedent ejaculation. The display of penile reflexes within 1 min after ejaculation suggests that the period of reduced sexual arousability following ejaculation is not due to reduced excitability in the spinal mechanisms controlling penile reflexes. In Experiment 4, 1 hr of penile-reflex elicitation had no effect on subsequent copulatory behavior. Thus, sexual stimulation may increase or decrease penile-reflex potential, but a reciprocal influence was not detectable.

Animals↗

PubMed1975

Plasma luteinizing hormone and testosterone in the adult male pig: 24 hour fluctuations and the effect of copulation.

Secretory patterns of LH and testosterone were characterized in the intact male miniature pig. All blood samples were taken from indwelling catheters. Hourly sampling was carried out over 24 h and during a morning period blood was collected for 2 h at 10 min intervals. No significant difference was detected in the plasma LH concentration on the basis of hourly sampling. Plasma testosterone was significantly (P less than 0-05) lower during the evening and night when compared with morning values. The second experiment was concerned with the pattern of plasma LH and testosterone concentrations before and after copulation. Blood sampling was performed at 10 min intervals. Plasma LH was significantly (P less than 0-001) raised for 30 min after copulation when compared with any 30 min period (0-120 min) before copulation. Plasma testosterone was not significantly altered for any 30 min period of the experiment (0-270 min). The data are interpreted as a possible mechanism for endocrine control of testicular function.

Animals↗

PubMed1978

Investigation of copulative activity in male rats in chronic experiment.

Copulative activity of 28 male Wistar rats was investigated for one year at 6 to 8 day intervals. Metholds have been worked out for the selection of sexually active males. It was found that it is possible to investigate copulative activity permanently in a selected population of male rats. The sexual activity index number of intromissions/time of ejaculation can be applied to the 15-minute test. In order to evaluate individual differences observed during the experiments, the ratio positive experiments/all experiments has been used. During a one-year experimental period (791 experiments altogether) mean latency time was 56'', and that of the ejaculation 7'10''. The average number of intromissions was 7.89, and that of attempts 3.41. Ejaculation occurred 575 times. The average sexual activity index was 1.1. There was no seasonal fluctuation in copulative activity.

Animals↗

PubMed1977

Transmission of Nosema kingi to offspring of Drosophila willistoni during copulation.

Transmission of the microsporidian Nosema kingi to offspring of Drosophila willistoni during copulation was investigated. Offspring from matings of infected females and non-infected males, infected males and non-infected females, and both infected females and males were parasitized with N. kingi. 28% of the offspring were infected when the parents mated immediately after exposure to the parasite. However, 43--93% of the offspring were infected with the microsporidian when copulation was delayed 2 weeks post-infection.

Animals↗

PubMed1977

5-hydroxytryptamine depletion with para-chlorophenylalanine: effects on eating, drinking, irritability, muricide, and copulation.

Forty-four male rats were tested for eating, drinking, irritability, and copulation before and after intraperitonial para-chlorophenylalanine (PCPA) or control injections. Eleven of these rats were tested for muricide before and after PCPA injections (Group 1), while 18 others were tested only after PCPA injections (Groups 2). Group 1 rats received four 350 mg/kg PCPA injections spaced 6 days apart and showed hyperdipsia, weight loss, and a 24% increase in muricide. Group 2 rats received five daily 100 mg/kg PCPA injections repeated 11 days later and showed hyperdipsia and weight loss; in addition, 78% of them killed mice. Neither group showed significant changes in copulation. At the end of the experiment, t6 rats from Group 2 that were irritable and killed mice were injected intraperitonially with 5-hydroxytryptophan (80 mg/kg). Five of these rats lost their irritability and four stopped killing. The various behavioral changes were not corrleated significantly either with each other or with the degree of 5-hydroxytryptamine depletion. This tentatively suggests that PCPA may produce its effects on behavior by other means in addition to 5-hydroxytryptamine depletion.

Aggression↗

PubMed1975

Suppression of precocial copulation by progesterone implants in the male chick forebrain.

Precocial copulation in 2-wk.-old male chicks, described behaviorally as free mount, tread, posterior contact, waggle, peek, and seize, was developed through hand-training experience and androgen treatment. Crystalline progesterone was then implanted in various forebrain or midbrain regions. Results indicated that progesterone inhibited copulatory behavior when placed in the periventricular areas of the preoptic-hypothalamic continuum. Progesterone implants in the preoptic lateral forebrain bundle regions also suppressed precocial copulation. Forebrain implants of cholesterol did not result in copulatory inhibition. The suppression of copulatory behavior was not accompanied by loss of weight or deficits in general activity or comb growth. These data indicate that brain regions responsible for progesterone-induced copulatory inhibition are similar in neuroanatomical distribution to those involved in testosterone-induced copulatory activation.

Age Factors↗

PubMed1975

The septum: neural systems involved in eating, drinking, irritability, nuricide, copulation, and activity in rats.

Eating, drinking, irritability, muricide, and copulation were measured in 45 male rats before and after one of three coronal knife cuts in the septal region or a control operation; in addition, activity was measured postoperatively. (a) Cuts posteroventral to the septum resulted in slight hypophagia, marked hyperdipsia, irritability, asexuality, and decrease in activity. (b) Cuts of the fornix resulted only in slight decrease in activity. (c) Cuts through the anterior septum resulted in irritability, slight hyposexuality, and slight decrease in activity. No significant correlations between the various behavioral effects were found. It was suggested that the neural pathways mediating eating, drinking, irritability, muricide, copulation, and activity are relatively distinct and that neural activity in the septal region probably does not influence behavior in any unitary fashion.

Aggression↗

PubMed1975

Pregnancy in cactus mice: effects of prolonged copulation.

The postejaculatory copulations of cactus mice are demonstrated to function in facilitating neuroendocrine responses necessary for pregnancy. Whereas estrous cycles were altered after just 10 percent of the tests terminated after one ejaculatory series, females became either pregnant or pseudopregnant after 80 percent of tests continued at least to sexual satiety (30 minutes with no copulations).

Animals↗

PubMed1977

Effects of repeated morphine administration on copulation and on the hypothalamic-pituitary-gonadal axis of male rats.

Adult male rats were administered morphine twice a day for 45 days and the effects of morphine on the copulation rate, the weight of various organs, and on the hypothalamic-pituitary-gonadal axis were examined. Morphine administered rats showed a loss of weight, hypertrophy of the adrenals, decreased weight of accessory sex organs, low sperm count, and decreased copulation rate. The contents of the luteinizing hormone releasing hormone in the hypothalamus and the luteinizing hormone in the pituitary remained unchanged. Serum luteinizing hormone and testosterone levels decreased, but serum follicle-stimulating hormone levels increased. These results suggest that morphine inhibits the hypothalamic-pituitary-gonadal axis and causes a diminution in the number of fertilizations of the partner females.

Animals↗

PubMed1979

[Supression by copulation of the inhibitory effect of p-chlorophenylalanine on rat ovulation (author's transl)].

The effect of copulating on reflex ovulation was studied in rat. The effect of PCPA (300 mg/kg, i.p.) on ovulation and reproduction was compared by evaluating number of oocytes in tubes, histologic features of ovaries, vaginal cycle, insemination, fertilization and number of embryos per rat. PCPA, administered on 9th and 16th h of the estrus phase, totally inhibits ovulation, stimulates reproductive behaviour and prolongs the estrogenic phase. When the animals are kept in copulatory conditions for 16 or 46 hours, the inhibition induced in ovulation disappears to the extent that 60% of the rats become pregnant though the number of embryos is under that of the control group. The farther the treatment with PCPA within the same cycle in the ovulatory period, the greater the inhibitory effect on ovulation is and the lesser the neutralizing effect produced by reflexes related to copulation. Administration of PCPA at the 16 hour of the diestrus causes a greater increase in the average number of embryos-as compared to administration at the 9 hour. In periods longer than 48 hours before ovulation, the inhibition brought about by PCPA is not suppressed by copulatory conditions kept for 16 or 24 hours and is only neutralized if they are kept during a complete cycle. Those treated with PCPA in the diestrus phase and maintained in copulatory conditions for 46 hours, present a higher average of embryos than those maintained in similar conditions for 16 hours.

Animals↗

PubMed1976

Deleterious effects of copulation in Drosophila females as a function of growth temperature of both sexes.

In Drosophila females, copulation always results in a reduction of longevity but the gravity of the phenomenon varies according to growth temperature. The harmful effect of adult males, or aggressiveness, is maximum when growth took place at a middle temperature. Female sensitivity, on the other hand, is at a maximum when larvae were reared at exteme, low or high, temperatures.

Aggression↗

PubMed1975

Copulation in spiders: experimental evidence for fatigue effects and bilateral control of palpal insertions.

Male lycosid spiders were prevented from using one palp during the first third of copulation by a sling that we then cut to free the palp. Initial insertion durations of the treated palp were significantly shorter than those shown concurrently by the much-used normal palp; they showed temporal patterning unaffected by use of the normal palp. Data indicate that there are relatively independent control mechanisms for each palp and support the hypothesis that fatigue causes the increased duration of successive palpal insertions. Our data also suggest that normal matings terminate due to maximal use of either palp by the male.

Animals↗

PubMed1977

Social-olfactory experience and initiation of copulation in the virgin male rat.

Two experiments examined the role of olfactory sensation for initiation of normal copulatory behavior of mature male rats. Experiment 1 compared copulatory performance of peripherally anosmic social isolates with that of intact isolate controls. The results revealed significantly lower mounting, intromission, and ejaculation frequencies of the anosmic group and suggested that nonolfactory cues attain significance via an associative-learning process. Experiment 2 compared three social isolate groups of mature males with varying sexual experience prior to anosmia. Four 1-hr tests were conducted at 5-day intervals. The results indicated comparable copulatory performance of the experienced groups and absence of copulation by the majority of the nonexperienced group. With a 12-day continuous exposure to intact females, all noncopulators eventually impregnated. The results are discussed with reference to the requirement of social experience for initiation of normal sexual performance in the male rat.

Animals↗