Our aim was to evaluate hemodynamic and respiratory responses to different levels of hypoxia and hypercapnia in conscious intact or carotid body-denervated rats.
METHODS: Male Wistar rats were submitted to bilateral ligature of carotid body arteries (or sham-operation) and received catheters into the left femoral artery and vein. After two days, each animal was placed into a plethysmographic chamber and, after baseline measurements of respiratory parameters and arterial pressure, each animal was subjected to three levels of hypoxia (15, 10 and 6% O-2) and hypercapnia (10% CO2).
RESULTS: The results indicated that 15% O-2 decreased the mean arterial pressure and increased the heart rate (HR)
in both intact Bafilomycin A1 order IWR-1-endo ic95 (n=8) and carotid body-denervated (n=7) rats. In contrast, 10% O-2 did not change the mean arterial pressure but still increased the HR in intact rats, and it decreased the mean arterial pressure and increased
the heart rate in carotid body-denervated rats. Furthermore, 6% O-2 increased the mean arterial pressure and decreased the HR in intact rats, but it decreased the mean arterial pressure and did not change the HR in carotid body-denervated rats. The 3 levels of hypoxia increased pulmonary ventilation in both groups, with attenuated responses in carotid body-denervated rats. Hypercapnia with 10% CO2 increased the mean arterial pressure and decreased HR similarly in both groups. Hypercapnia also increased pulmonary ventilation in both groups to the same extent.
CONCLUSION: This study demonstrates that the hemodynamic and ventilatory responses varied according to the level of hypoxia. Nevertheless, the hemodynamic and ventilatory responses to hypercapnia did not depend
on the activation of the peripheral carotid chemoreceptors.”
“Contents This paper reviews recent data and concepts on the development of inflammation in the reproductive tract of dairy cows during the first 2 months after calving. The incidence of metritis is typically 10-20%, with 5-15% of LCL161 cows having purulent vaginal discharge (PVD), 15-40% having cervicitis approximately 1 month after calving, and 10-30% having cytological endometritis between 1 and 2 months after calving. Endometritis, cervicitis and PVD are distinct conditions, each of which is associated with significantly increased time to pregnancy, and affected cows often have more than one of these conditions. Cumulatively, 35-50% of cows have at least one form of pathological reproductive tract inflammation between 3 and 7 weeks postpartum. It is hypothesized that reproductive tract disease represents a failure of the immune system to switch fast enough or far enough from the down-regulated state necessary for maintenance of pregnancy to a heightened state of function for postpartum clearance of bacteria and tissue debris and then to a ‘quiet’ state 3-4 weeks later.