Raphe obscurus neurons participate in thermoregulation in rats.

In mammalian, several evidences suggest that central serotonin participates in thermoregulation. Nucleus raphe obscurus (NRO), a serotonergic nucleus, has been recognized to be the source of generation of various hemodynamic patterns in different behavioral conditions, but its involvement in thermoregulation is unclear. In the present study, extracellular action potentials of NRO neurons were recorded in anesthetized rats, which were submitted to cold and warm stimuli in the tail.

High-frequency transcutaneous electrical nerve stimulation reduces pain and cardio-respiratory parameters in an animal model of acute pain: participation of peripheral serotonin.

The objective of this study was to investigate the effect of high-frequency transcutaneous electrical nerve stimulation (HF-TENS) in antihyperalgesia, assessed through changes of sciatic nerve activity and its effects on cardiorespiratory parameters, using formalin-induced nociception in anesthetized rats. The animals were divided into formalin (FORM) and HF-TENS groups. All rats received injections of 5% formalin (50 μl, right hind-paw).

The role of magnesium sulfate in prevention of seizures induced by pentylenetetrazole in rats.

Magnesium sulfate (MgSO₄) has been used to prevent seizures in eclampsia. This study examined the central effects of MgSO₄ on different types of pentylenetetrazole (PTZ)-induced seizures. Male Wistar rats were submitted to intracerebroventricular (ICV) administration of MgSO₄ at different doses followed by intraperitoneal administration of PTZ.

Acute cardiorespiratory effects of intracisternal injections of mercuric chloride.

The present studies were conducted to changes arising from mercury poisoning in the central nervous system (CNS), with a focus on determining the receptors and neurotransmitters involved. Currently, little is known regarding the neurological basis of the cardiopulmonary effects of mercury poisoning. We evaluated changes in systolic arterial pressure (SAP), diastolic arterial pressure (DAP), respiratory rate (RR) and heart rate (HR) following a 5 μl intracisternal (i.