Effects of tamoxifen metabolites on fertility of male rat

The effects of chronic oral administration of tamoxifen citrate, at a dose of 0.4 mg/kg/day, were compared to those of subcutaneous (s.c) administration of tamoxifen citrate, 4-hydroxy tamoxifen, N-desmethyl tamoxifen and intermittent oral tamoxifen administration on the fertility of the male rat and its post reversal progeny. The fertility parameters of 120 day-treated male rat sires from all groups and post reversal male F1 progeny of tamoxifen-treated sires were assessed. Chronic tamoxifen treatment via oral or s.c. routes reduced the fertility of the male rat, weights of accessory sex glands, serum luteinizing hormone, and testosterone levels without altering potency or sperm counts. However, antifertility effects of s.c. treatment were comparatively more consistent than those of oral treatment. 4-hydroxy and N-desmethyl tamoxifen failed to produce significant antifertility effects in the male rat. The antifertility effects of intermittent oral treatment were more sustained than those of chronic oral tamoxifen treatment. It is inferred that hepatic metabolism of tamoxifen interferes with its antifertility effects via oral route and that the parameters affected by chronic oral exposure in the male sires are completely reversed in progeny ensuing after an adequate period of drug withdrawal.     

The effects of tamoxifen on the vaginal epithelium in postmenopausal women

Although increased vaginal discharge occurs with treatment, clinicians often presume the effects of tamoxifen on the vaginal epithelium are antiestrogenic. We studied 16 postmenopausal women before they began tamoxifen treatment, at 6 months, and then at annual intervals for up to 6 years. Vaginal scrapings for cytology smears and maturation values (MV) for these were performed. MV scores increased by a mean of 32% and these were predictably related to baseline values, with greater increases seen when there were lower scores before treatment. Only one woman with an MV of 0 before treatment had no significant changes with 3 years' treatment. The effects of tamoxifen on the vaginal epithelium are influenced by the baseline hormonal milieu and are maturational in the majority of postmenopausal women.     

Clitoral blood flow increases following vaginal pressure stimulation

The vascular responses of clitoral arteries to vaginal pressure stimulation in 10 volunteer women were evaluated by Doppler ultrasonography. Pressure stimulations (20–160 mm Hg) along the lower third of the vagina increased blood velocity and flow into clitoral arteries in 9 of the 10 women. The latency and duration of the Doppler responses ranged from 0.1 to 1.6 sec and from 3.2 to 9.5 sec, respectively, and the response was associated with a blood flow increase of 4 to 11 times the baseline prestimulation level. This response parallels that recorded in the cavernous arteries in men when a similar range of pressure stimulations are applied to the glans penis. Similar responses evoked in the male and female suggest a sexual synergy that may occur during intercourse in that such physiological responses and reflexes may be reciprocally reinforced.     

Utero-ovarian morphology and blood flow after tubal ligation by the Pomeroy technique

OBJECTIVES: The objectives of this study were to evaluate ovarian sonographic morphology and pelvic blood flow in patients who had undergone bilateral tubal ligation by the Pomeroy technique. DESIGN: Twenty women who had undergone bilateral tubal ligation during cesarean section by the Pomeroy techniques were compared to 20 matched controls who had undergone cesarean section alone. Ovarian morphology as well as ovarian and uterine pulsatility index (PI), resistance index and peak systolic velocity were evaluated using transvaginal sonography and Doppler velocimetry. RESULTS: Patients post tubal ligation by the Pomeroy technique were found to have a significantly higher rate of polycystic appearance of the ovaries (60% vs. 5%; p < 0.005). Six patients (30%) had post tubal ligation symptoms, as compared to none of the controls. Five of the six symptomatic tubal ligation patients (83%) had ovarian polycystic appearance, which was not significantly different than asymptomatic patients. Ovarian artery PI was significantly higher in symptomatic patients (2.7 +/- 1.9) compared to asymptomatic patients (1.5 +/- 0.9) (p < 0.05). CONCLUSIONS: We therefore conclude that patients post bilateral tubal ligation by the Pomeroy technique may acquire an ovarian polycystic appearance and increased ovarian PI, which may be associated with a tendency to develop post tubal ligation symptoms.     

Effects of acute pesticide poisoning on blood clotting in the rat

Male Sprague-Dawley rats were treated with 1ml of diazinon or malathion, 1750 ppm given orally by gavage. Clotting determinations included the prothrombin time, partial thromboplastin time, fibrinogen, and coagulation factors II, V, VII, and X, plus the hematocrit and platelet count. The results suggest that insecticides influence the clotting times of rats ingesting these insecticides even after as short a time span as 2 hr.     

Effects of infrasound on gastric mucosal blood flow in rats

To clarify the effects of infrasound on gastric mucosal blood flow, rats were exposed to infrasound for 20 minutes. The sounds were pure tones of 8, 16 and 32 Hz, at sound levels ranging from 80 dB to 130 dB. Gastric mucosal blood flow was determined by the inhaled hydrogen gas clearance method. Norepinephrine and epinephrine concentrations in the plasma were also measured. The exposed rats showed decreased gastric mucosal blood flow with increasing sound levels of infrasound at each octave-band frequency. To significantly decrease the gastric mucosal blood flow, infrasound at 32, 16 and 8 Hz needed sound levels of 100, 110 and 130 dB, respectively. These findings suggest that, as the frequency of infrasound decreases, an increased sound level is necessary to decrease the gastric mucosal blood flow. The norepinephrine and epinephrine concentrations in the plasma were 0.65±0.47n.g/ml and 0.35±0.43 ng/ml, respectively, in the control rats, while the corresponding values were 0.91±0.87 ng/ml and 0.74±0.81 ng/ml, respectively, in the exposed rats. There were significant increases (p>0.05) in norepinephrine and epinephrine. Thus, it is probable that exposure to infrasound stimulates the sympathetic nervous system and causes a decrease in gastric mucosal blood flow.     

Effect of capsaicin on gastric acid secretion and mucosal blood flow in the rat.

The effect of capsaicin, a pungent ingredient in capsicum fruit, upon gastric acid secretion and mucosal blood flow was assessed in the anesthetized rat. At each 15 minute interval, 0.3 ml saline solution, with or without various doses of pure synthetic capsaicin (the doses varied from 50 to 2,000 microgram/kg rat) was delivered into the gastric lumen via a gastric fistula. The gastric contents were withdrawn after 15 minutes for acid assay and replaced with a new saline solution. Capsaicin of increasing doses (up to 1,000 microgram/kg) progressively increased the acid output. Gastric inhibitors hexamethonium and atropine, completely abolished the acid secretion induced by capsaicin whereas secretin only partially reduced such a response. The systemic blood pressure was not affected by the capsaicin or the method employed. However, the aminopyrine clearance which was the indicator of the gastric mucosal blood flow increased in accordance with the increase in the acid output. It is suggested that the effect of capsaicin on the acid secretion and mucosal blood flow is by the release of endogenous gastric secretagogues which increase both tissue perfusion and the secretory activity.     

Orgasm in women in the laboratory—quantitative studies on duration,intensity, latency,and vaginal blood flow

Sexual arousal by clitoral self-stimulation was used by healthy, young adult women volunteers (n =28) to induce orgasm in the laboratory. The duration of the orgasm was obtained using the subject's verbal indication of its start and finish. The estimated duration and the subjective experience of the orgasm self-graded on a 5-point scale were also obtained in a number of subjects. Vaginal blood flow was assessed by the power consumption needed to keep a heated oxygen electrode, held on the vaginal wall by suction, at a constant temperature. The mean measured orgasm duration was 19.9 seconds (SD, ± 12, n =26). For 14 subjects, their estimate of the duration of their orgasms (12.2 ± 9.8 seconds, mean ± SD) was greatly underestimated compared with the measured duration (26 ± 14.6 seconds). This result indicates that data obtained on the duration of orgasm from questionnaires or interviews have suspect validity. The measured duration of the orgasms was not significantly correlated with the subjective grading. The increase in vaginal blood flow at orgasm was not significantly correlated with the subjective gradings of orgasm (n =18), the orgasm latency (time taken to induce orgasm, n =18), or the measured duration of orgasm (n =14). This research was funded in part by a grant from the Novo Fund, Copenhagen, Denmark.     

Possible improvement of the clitoral and vaginal blood flow using a somatostatin analog in chronic spinalized Sprague-Dawley rats

We evaluated the effect of a somatostatin analog (octreotide) on clitoral and vaginal blood flow following suprasacral spinal cord injury (SCI) in rats. Twenty-four spinalized female Sprague-Dawley rats were randomized into 4 equal groups. The first group served as control paraplegics. The other three groups received octreotide (60 micrograms/day/4 weeks) immediately, 2 weeks, and 4 weeks following SCI. At the end of the experiment, a laser Dopper was used to measure blood flow changes following clitoral and pelvic nerve plexus stimulations. Marked decreases in both clitoral and vaginal blood flow in the control paraplegics were recorded. Significant increases (p < 0.05) in both clitoral and vaginal blood flow were recorded in animals that received octreotide; however, the increase was marked in the animals that received the drug immediately following SCI. Improvement in the clitoral and vaginal blood flow of spinalized rats using octreotide indicates that octreotide may be helpful for patients with SCI.     

Effects of contraceptive vaginal ring treatment on vaginal bacteriology and cytology

The presence of aerobic and anaerobic bacteria, yeasts and mycoplasma/ureaplasma was investigated in seventeen women before and after six months use of a contraceptive vaginal ring releasing levo-Norgestrel and estradiol and in 16 women using an oral contraceptive containing levo-Norgestrel and ethinylestradiol. Apart from an increase in yeasts in both groups, no significant changes in the vaginal bacteriology could be found.Vaginal smears were examined before and during treatment for up to two years in a group of 120 women participating in a clinical trial of the contraceptive vaginal ring. No changes in the squamous epithelium or cylinder cells were found. The amount of leucocytes increased in the smears.The results indicate that use of the contraceptive vaginal ring does not affect the bacterial ecology of the vagina. The increase in leucocytes indicates a weak inflammatory reaction which might explain the increase in vaginal discharge often observed by women using the contraceptive vaginal ring.     

Effects of unilateral ovariectomy with compensatory hypertrophy on ovarian blood flow, oxygen consumption and progestin secretion in the 16-day pregnant rat

Stimulated ovulation with resultant multiple corpora lutea (CL) can result in lower progesterone levels than expected from the increased luteal tissue mass. Unilateral ovariectomy (ULO) was used to increase CL number in rats and determine whether this would compromise luteal tissue blood flow, oxygen consumption and progestin secretion. All investigations were performed in vivo, using a venous outflow technique on Day 16 of gestation, when progesterone secretion is maximal. ULO, performed before pregnancy, doubled CL number and total CL mass in the remaining ovary of six treated compared to five control rats. Growth of CL was not affected. The rate of ovarian blood flow (microL min(-1) mg CL(-1)) fell to 47% of control levels in ULO animals and progesterone secretion (microg h(-1) mg CL(-1)) to 68%. Secretion of the minor progestin, 20alpha-hydroxypregn-4-en-one was not affected. Tissue oxygen consumption was maintained despite the reduction in blood flow by an increase in oxygen extraction from arterial blood. These results suggest that overcrowding of CL in ULO-stimulated rat ovaries compromises luteal tissue blood flow and subsequently progesterone secretion.     

Effects of prolonged exposure to dietary DDT and PCB on rat liver morphology

Livers from mature female rats exposed for up to 36 weeks to dietary levels of Aroclor^® 1242 (75 or 150 ppm) and/or commercial grade DDT (75 or 150 ppm) were compared to those from animals receiving basal diets. In earlier studies, reproductive effects of the test substances were assessed. Moreover, the markedly abnormal gross appearance of the livers led to examination of the hepatic effects of PCB and DDT in more detail, at both the light microscope (LM) and electron microscope (EM) levels.Light microscopy revealed focal liver cell necrosis in rats fed PCB, DDT, and PCB-DDT combinations. Higher levels of PCB (150 ppm) increased the severity of necrosis. Feeding both DDT and PCB produced similar effects at 75 ppm, and caused atypical centrolobular regeneration, occasionally forming nodules resembling small tumors. The experimentally induced injury was associated with the marked accumulation of iron-containing pigment in hepatocytes and Kupffer cells.Electron micrographs demonstrated the presence of whorl structures (myelin figures) within liver cell cytoplasm, and for the first time clearly illustrated the endocytotic expulsion of these membranous whorls from hepatocytes into the bile canaliculi and sinusoids. Other ultrastructural changes were similar to those previously reported in rat livers injured by several hepatotoxic substances. Mitochondria enclosed by or projecting into large non-lipid vacuoles were present in several experimental groups.The electron micrographs provide the most convincing evidence to date to support the hypothesis that myelin figures may be the vehicle whereby the cell rids itself of specific hepatotoxic substances.     

Catecholamine-mediated reduction in uteroplacental blood flow in the diet-restricted, term-pregnant rat

To determine whether the reduction in maternal placental blood flow associated with malnutrition during pregnancy results from alpha-adrenergic vasoconstriction, we measured cardiac output, uteroplacental blood flow and uteroplacental vascular resistance in ad libitum-fed and in 50% diet-restricted term-pregnant rats, using radioactive-labeled microspheres before, and again after, alpha-adrenergic receptor blockade with phenoxybenzamine. Uteroplacental blood flow in the diet-restricted rats was 40% lower than that of the ad libitum-fed rats, before phenoxybenzamine. Phenoxybenzamine caused a 50% reduction in mean blood pressure in both the ad libitum-fed and diet-restricted rats, but did not alter cardiac output. Phenoxybenzamine decreased preplacental vascular resistance in the diet-restricted rats, resulting in no significant reduction of placental blood flow. In the ad libitum-fed rats, on the other hand, phenoxybenzamine did not alter preplacental vascular resistance, and placental blood flow decreased 45% with the fall in blood pressure. Myometrial vascular resistance was unaffected by phenoxybenzamine in either group, and myometrial blood flow decreased with the fall in blood pressure in both groups. Thus, the decreased uteroplacental blood flow associated with diet restriction is the result of increased uteroplacental alpha-adrenergic vasomotor tone.     

番茄红素对高脂血症大鼠血脂及红细胞的影响

目的 研究番茄红素对高脂血症大鼠血脂及红细胞的影响.方法 成年雄性SD大鼠48只,根据总胆固醇(TC)水平、体重随机分为6组:正常对照组(A组),基础饲料喂养;高脂模型组(B组),高脂饲料喂养;阳性药物对照组(C组),高脂饲料+氟伐他汀钠10 mg·kg~(-1)·d~(-1);番茄红素D组(高脂饲料+番茄红素11 mg·kg~(-1)·d~(-1))、E组(高脂饲料+番茄红素22 mg·kg~(-1)·d~(-1))、F组(高脂饲料+番茄红素44 mg·kg~(-1)·d~(-1)),灌胃处理.各组大鼠均于实验开始第0、1、3周末取尾静脉血检测血清TC、甘油三酯(TG)等的含量.第3周末检测血红蛋白(HGB)、红细胞计数(RBC)等相关参数.结果 高脂饲料喂养1周后,大鼠形成高脂血症;实验结束,A、B、C、D、E、F组TC分别为(1.31 4-0.05)、(19.40 ±0.54)、(4.66 ±0.07)、(7.18 ±0.06)、(5.30 ±0.28)、(4.49±0.23)mmol/L(F=4395.72,P=0.00);TG分别为(0.42 ±0.01)、(2.29±0.42)、(0.69 ±0.03)、(1.10 ±0.05)、(0.63 ±0.02)、(0.62 ±0.04)mmol/L(F=127.26,P=0.00);HGB分别为(143.13 ±6.33)、(112.63 ±2.56)、(124.75 ±3.62)、(124.63 ±7.78)、(132.38 ±6.41)、(142.13 ±5.54)g/L(F=34.14,P=0.00);RBC分别为(6.75 ±0.60)× 10~(12)/L、(5.08 ±0.75)×10~(12)/L、(7.14±0.82)×10~(12)/L、(5.94 ±1.09)× 10~(12)/L、(6.18 ±0.36)× 10~(12)/L、(7.31 ±0.58)× 10~(12)/L(F=10.35.P=0.00).结论 番茄红素可能通过调节血脂和抗氧化而发挥其对红细胞的保护作用.     

Effects of vibration, noise and restraint on heart rate, blood pressure and renal blood flow in the pig

Pigs and other farm animals are usually transported at least once during their lives; for example, all meat animals are finally taken to the abattoir for slaughter. The vibration, noise and handling associated with such transportation is usually novel to the animals, and therefore constitutes a potential 'stressor'. Such adverse stimuli may trigger physiological and psychological changes which rapidly produce profound changes in blood flow to peripheral organs, particularly the kidney, whose blood vessels are richly supplied with sympathetic nerve fibres. In the present study, ultrasonic techniques have been used with chronically implanted flow sensors for measuring heart rate (HR) and changes in renal blood flow (RBF) in conscious, freestanding and unanaesthetized pigs to monitor their cardiovascular responses to vibration, noise and various handling procedures. In addition, arterial blood pressure (BP) was measured via a catheter placed in the carotid artery. To ensure that vibration and noise could be accurately reproduced, a transport simulator (TS) was constructed in the laboratory. A small decrease of approximately 5% was observed in RBF during the first few minutes of exposure to vibration and noise, but this returned to the control levels monitored in undisturbed animals within a few minutes. Thereafter, RBF became significantly elevated for the remaining period of exposure to vibration and noise. In contrast, HR remained significantly increased throughout. BP was not significantly changed as a result of the experimental manipulation. Restraint and handling of the animals appeared to cause maximal disturbance. HR and BP were more than doubled compared with the resting value, but there was a concomitant marked decrease in RBF.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of oral contraceptive pill use on vaginal flora and vaginal epithelium

The objective of this study was to examine the effect of oral contraceptive (OC) use on vaginal discharge, epithelium, and flora. Thirty women who planned to use OC for contraception were evaluated before and 2 months after the start of OC use. At both visits, genital symptoms and exposures were assessed by questionnaire; vaginal signs were assessed by speculum examination and colposcopy; vaginal microflora was evaluated by quantitative culture; and a vaginal biopsy was obtained for histopathologic evaluation. Variables were compared between the initial visit and after 2 months of OC use. It was found that OC use did not change the gross, colposcopic, or histologic appearance of the vaginal epithelium or characteristics of vaginal or cervical discharge. Vaginal flora essentially remained unchanged after 2 months of OC use, except that a small decrease occurred in the number of subjects with > or =10(5) colony forming units/mL of H(2)O(2) producing Lactobacillus from 16 at baseline to 9 (p = 0.04) and in the total number of subjects with Ureaplasma urealyticum from 17 at baseline to 10 of 29 (p = 0.04). The results indicate minimal effect of OC use on the vaginal epithelium and vaginal and cervical discharge, and a small effect on vaginal flora.     

Effects of tobacco smoke inhalation on capillary blood flow in human skin

To measure the effects of tobacco smoke inhalation on capillary blood flow in human skin, 20 female tobacco smokers consented to smoke three cigarettes with nicotine levels of 0.50, 0.98, and 1.90 mg per cigarette, each on a separate occasion. Measurements of blood flow velocity and vascular diameter were made along the venous limb of capillaries within the nailfold skin of the third finger via videomicroscopy before and for 5 min after the smoking of each cigarette. Capillary blood flow (CBF) was calculated as a product of capillary cross-sectional area and flow velocity. Resting pre-smoke CBF for all experiments combined averaged 4.7 X 10(4) mu 3/sec. All three cigarettes elicited a significant reduction in CBF with the maximal effect within the first 2 min of the post-smoke period (p less than or equal to .05). Respective CBF values during this time averaged 3.6, 3.4, and 2.7 mu 3/sec for the low-, medium-, and high-nicotine cigarettes. Although the data suggested a downward trend in CBF with increasing nicotine levels, the post-smoke values were not significantly different among the three cigarettes. It is concluded that acute tobacco smoke inhalation reduces CBF in human skin, but the effect is not related to the nicotine content of the cigarettes. The changes in cutaneous CBF observed with tobacco smoking are less compared to reported effects of smoke inhalation on total digital blood flow.     

Effects of temperature on reductions in finger blood flow induced by vibration

Purpose  

To investigate how temperature influences changes in finger circulation induced by hand-transmitted vibration in healthy subjects, and the variability in individual response to both vibration and temperature.     

Effects of venesection on leg blood flow in claudicants with high-normal haematocrit

Patients with intermittent claudication frequently have high-normal levels of haematocrit and hence blood viscosity, which may contribute to decreased calf blood flow on exercise, and hence to the symptom of claudication. Reduction in haematocrit and viscosity by serial venesection in eight patients with stable claudication and high-normal haematocrit (mean 0.50) was performed, and the effects on claudication, calf blood flow, and calf oxygen delivery were studied. Following reduction in haematocrit to low-normal levels (mean 0.44), resting calf blood flow was unchanged; peak flow after ischaemic exercise increased slightly (+17%), but peak oxygen delivery (peak flow X haemoglobin concentration) was unchanged. Hence any increase in calf blood flow in the symptomatic leg is balanced by a decrease in oxygen-carrying capacity after venesection. No increase in claudication time would therefore be expected, and none was observed in the present study.