Activation of 5-HT1A receptors in the preBotzinger region has little impact on the respiratory pattern

作者：Radocaj Tomislav; Mustapic Sanda; Prkic Ivana; Stucke Astrid G; Hopp Francis A; Stuth Eckehard A E; Zuperku Edward J^*

来源：Respiratory Physiology & Neurobiology, 2015, 212: 9-19.

DOI：10.1016/j.resp.2015.03.005

• 5-HT receptors
• Control of breathing
• Respiratory neurons
• preBotzinger complex
• 5-HT1A receptors
• 8-OH-DPAT

The preBotzinger (preBotC) complex has been suggested as the primary site where systemically administered selective serotonin agonists have been shown to reduce or prevent opioid-induced depression of breathing. However, this hypothesis has not been tested pharmacologically in vivo. This study sought to determine whether 5-HT1A receptors within the preBotC and ventral respiratory column (VRC) mediate the tachypneic response induced by intravenous (IV) (+/-)-8-Hydroxy-2-diproplyaminotetralin hydrobromide (8-OH-DPAT) in a decerebrated dog model. IV 8-OH-DPAT (19 +/- 2 mu g/kg) reduced both inspiratory (I) and expiratory (E) durations by similar to 40%, but had no effect on peak phrenic activity (PPA). Picoejection of 1, 10, and 100 mu M 8-OH-DPAT on I and E preBotC neurons produced dose-dependent decreases up to 40% in peak discharge. Surprisingly, microinjections of 8-OH-DPAT and 5-HT within the VRC from the obex to 9 mm rostral had no effect on timing and PPA. These results suggest that the tachypneic effects of IV 8-OH-DPAT are due to receptors located outside of the areas we studied. Published by Elsevier B.V.

• 出版日期2015-7