Norepinephrine responses in rat renal and femoral veins are reinforced by vasoconstrictor prostanoids.

Norepinephrine (NE) responses are larger in renal and femoral veins compared to phenylephrine (PE). These differences may be due to the subtypes of adrenoceptor involved in these responses or to the involvement of local modulatory mechanisms. Therefore, the present study investigated in organ bath the adrenoceptor subtypes involved in the NE and PE responses in both renal and femoral veins as well as the influence of local mechanisms related to NO and to prostanoids upon these responses.

Could zinc prevent reproductive alterations caused by cigarette smoke in male rats?

The aim of the present study was to evaluate the effects of zinc on fertility through semen parameters, testosterone level and oxidative DNA damage to spermatozoa of rats exposed to cigarette smoke. Male Wistar rats (60 days old) were divided into four groups (n = 10 per group): control, cigarette-smoking (20 cigarettes per day), zinc (zinc chloride 20 mg kg⁻¹ day⁻¹) and zinc plus cigarette-smoking (zinc chloride 20 mg kg⁻¹ day⁻¹; 20 cigarettes per day). The treatment was applied for nine weeks and the following parameters were analysed: bodyweight, wet weights of the reproductive organs and the adrenal gland, plasma testosterone concentration, testicular function (seminal analysis and daily sperm production) and sperm DNA oxidative damage.

Effects of cigarette smoke exposure on pregnancy outcome and offspring of diabetic rats.

A total of 52 female Wistar rats were distributed into four groups: non-diabetic (G1) and diabetic (G2) exposed to filtered air; non-diabetic (G3) and diabetic (G4) exposed to cigarette smoke. Diabetes was induced by streptozotocin (40 mg/kg bodyweight, i.v.

Could neonatal testosterone replacement prevent alterations induced by prenatal stress in male rats?

The present study was designed to examine whether testosterone replacement is able to prevent some effects of maternal restraint stress--during the period of brain sexual differentiation--on endocrine system and sexual behavior in male rat descendants. Pregnant rats were exposed to restraint stress for 1 h/day from gestational days 18 to 22. At birth, some male pups from these stressed rats received testosterone propionate.

5alpha-reductase 2 inhibition impairs brain defeminization of male rats: reproductive aspects.

The present study was carried out to determine whether 5alpha-reductase 2 (5alpha-R2) metabolic pathway plays a key role in brain sexual differentiation. The inhibition of 5alpha-R2 by finasteride (20 mg/kg/day) from gestational day 19 to postnatal day 5 has long-term effects on sexual behavior and reproductive physiology detected only in adult life. Sexual maturation assessed by timing of preputial separation was unchanged.

Adrenergic response patterns in vas deferens isolated from rats under diurnal rhythms. Influence of stress.

The aim of this study was to verify, by means of functional methods, whether the circadian rhythm changes adrenergic response patterns in the epididymal half of the vas deferens isolated from control rats as well as from rats submitted to acute stress. The experiments were performed at 9:00 a.m.

Puberty installation and adrenergic response of seminal vesicle from rats exposed prenatally to hydrocortisone.

We investigated the effects of hydrocortisone during the prenatal period and its repercussion on puberty installation and adrenergic response of seminal vesicle in adult rats. The efficacy of the hydrocortisone treatment in reducing adrenal wet weight immediately after delivery in both the treated mothers and respective pups at birth may indicate impairment of the hypothalamus--pituitary--adrenal axis. This parameter was unchanged in the adult phase of these descendants, suggesting recuperation of this axis.