Midcervical vagotomy precludes respiratory response to novel anti-inflammatory and anti-tumour drug arvanil in rats.

Arvanil is a metabolically stable hybrid between anandamide and capsaicin. The present study was designed to test the role of the vagal pathway in post-arvanil respiratory and blood pressure responses. Respiratory and pressure changes evoked by an intravenous injection of arvanil were investigated in 21 urethane-chloralose anaesthetised and spontaneously breathing rats.

Supranodose vagotomy eliminates anandamide-evoked cardiorespiratory depression in anaesthetized rats.

Respiratory effects of an intravenous injection of anandamide were investigated in 19 urethane-chloralose anaesthetised and spontaneously breathing rats. In 10 neurally intact rats the effects of anandamide were checked to establish appropriate dose of the drug. In the second group, nine rats were challenged with anandamide while intact, following bilateral midcervical vagotomy and after subsequent supranodose vagotomy.

Cardiorespiratory effects of intravenous N-methyl-D-aspartate challenge in anaesthetized rats.

1. Experiments were performed to determine the effects of systemic application of N-methyl-d-aspartate (NMDA) on respiratory variables and blood pressure in 22 urethane/chloralose-anaesthetized, spontaneously breathing rats. 2.

Supranodose vagotomy precludes reflex respiratory responses to serotonin in cats.

Mediation of the respiratory reflex effects of an exogenous serotonin challenge goes beyond the lung vagi and is suggested to involve the nodose ganglia. In the present experiments the effects of an intravenous serotonin challenge on breathing pattern were studied in 8 pentobarbitone-chloralose anaesthetised cats. Bolus injection of serotonin oxalate (50 microg/kg) into the right femoral vein evoked prompt apnoea of 19.

Apnoeic responses to intracarotid nicotine challenge in anaesthetized cats.

To determine the effects of an intraarterial administration of nicotine on the occurrence of apnoea and the activity of rib cage respiratory muscles, we studied 31 anaesthetized, spontaneously breathing cats. Phrenic activity was used as an index of neural inspiratory drive. Activity of parasternal intercostal (PIM) and triangularis sterni (TS) muscles was recorded.

Action of serotonin on the laryngeal airway in anaesthetized cats.

The pulmonary chemoreflex induced by an intravenous injection of serotonin (5-hydroxytryptamine) in cats consists of prompt apnoea, bradycardia and hypotension, followed by rapid, shallow breathing. The present study had two purposes (1) to compare the effect of 5HT on ventilation and laryngeal resistance in cats and (2) to assess the role of laryngeal afferents in these responses. The effects of an intravenous injection of serotonin at a dose of 0.

Laryngeal constriction produced by capsaicin in the cat.

Pulmonary chemoreflex induced by an intravenous injection of capsaicin in cats consists of prompt apnoea, bradycardia and hypotension, followed by rapid, shallow breathing. The present study was designed to ascertain how much the post-capsaicin arrest of respiration and resumed breathing of pulmonary chemoreflex are contributed by the respiratory laryngeal resistance and by the sensory input from the larynx. The effects of intravenous injection of capsaicin at the dose of 0.

Respiratory effects of serotonin challenge to pulmonary and laryngeal circulation in anaesthetized cats.

Administration of serotonin (5-HT) to pulmonary circulation elicits prompt apnoea, followed by subsequent tachypnoea. The present study was designed to ascertain whether 5-HT challenge into the laryngeal artery will evoke the full constellation of this chemoreflex and to examine the role of laryngeal sensory input and importance of vagal afferents in the respiratory sequelae. The experiments were done on 10 anaesthetized, spontaneously breathing cats.

Effects of vagal and laryngeal afferents on apnoeic response to serotonin in cats.

Intravenous serotonin (5-HT) elicits apnoea followed by subsequent, shallow tachypnoea. The present study was designed to ascertain whether laryngeal afferents play a role in the respiratory reflex response. Administration of 5-HT into the femoral vein (i.

Depression of ventilation by dopamine in cats: effects of bilateral cervical sympathetic and vagal trunk section.

The contribution of sympathetic and vagal inputs to ventilatory depression induced by dopamine was studied in eighteen anaesthetized, spontaneously breathing, normoxic cats. Breathing was via a tracheostomy. Dopamine (20 micrograms (kg body wt)-1) was injected intravenously in the intact animal, then after section of the cervical sympathetic trunks, and finally after midcervical vagotomy.