Cerebrovascular reactivity after cessation of menopausal hormone treatment.

OBJECTIVE: Women who are currently using menopausal hormone therapy (MHT) have higher cerebrovascular reactivity when compared with postmenopausal women who are not taking MHT; however, the effect of cessation of MHT on cerebrovascular reactivity is not known. Given that MHT can have structural and activational effects on vascular function, this study was performed to characterize cerebrovascular reactivity following cessation of MHT in women at low risk for cerebrovascular disease. METHODS: Cerebrovascular reactivity was measured in a subset of women from the Kronos Early Estrogen Prevention Study (KEEPS) 3 years after cessation of the study drug (oral conjugated equine estrogen, transdermal 17ß-estradiol, or placebo [PLA]). RESULTS: Age, body mass index, and blood pressure were comparable among groups. At rest, the middle cerebral artery velocity (MCAv), cerebrovascular conductance index, mean arterial pressure, and cerebral pulsatility index did not differ among groups. Slope-based summary measures of cerebrovascular reactivity did not differ significantly among groups. However, utilizing repeated-measures modeling, there was a significant upward shift in MCAv responses (p = 0.029) in the combined MHT group compared with the PLA group. CONCLUSION: MHT has a marginal sustained effect on cerebrovascular reactivity when measured 3 years after cessation of hormone treatment.

Canid sex attractant studies.

Behavioral studies using anestrous female beagles, and olfactory tests with dogs in the absence of females, indicate that methylp-hydroxybenzoate cannot be considered a key sexual attractant for male beagles, even though this compound has been found in estrous vaginal secretions.

Some volatile constituents of female dog urine.

The volatile compounds from female beagle urine, across the state of estrus, were examined by headspace gas chromatography and mass spectrometry. The major constituents identified were methyl propyl sulfide, methyl butyl sulfide, and acetone. Nine minor constituents, including trimethyl amine and five disulfides, were identified. Two of the unidentified minor constituents may possibly be associated with the state of estrus.

Coyote estrous urine volatiles.

Samples of female coyote urine were taken once or twice each week during the winter and spring for two years. Headspace analysis was employed with Tenax GC trapping and GC-MS. Tenax trapping was started in less than 1 hr after sampling, and mild conditions were used to minimize losses of highly volatile and labile compounds. Thirty-four compounds were identified. They include sulfur compounds, aldehydes and ketones, hydrocarbons, and one alcohol. The principal constituent is methyl 3-methylbut-3-enyl sulfide, which usually comprised 50% or more of the total volatiles observed. The concentration of many constituents varied widely. This appeared to be quasiperiodic for five of the constituents, with a period of a few weeks, and with pronounced maxima at the peak of estrus. Apparently these compounds are 3-methyltetrahydrothiophene, methyl 3-methylbutyl sulfide, octanal, dodecanal, and bis(3-methylbut-3-enyl) disulfide. One or more of these compounds may have pheromonal activity in coyote relationships.