| Full text | |
| Author(s): |
Almeida, Jeferson
[1, 2]
;
Oliveira, Leandro A.
[1, 2]
;
Benini, Ricardo
[1, 2]
;
Crestani, Carlos C.
[1, 2]
Total Authors: 4
|
| Affiliation: | [1] Joint UFSCar UNESP Grad Program Physiol Sci, Sao Carlos, SP - Brazil
[2] Sao Paulo State Univ UNESP, Lab Pharmacol, Sch Pharmaceut Sci, Araraquara, SP - Brazil
Total Affiliations: 2
|
| Document type: | Journal article |
| Source: | Brain Research; v. 1710, p. 109-116, MAY 1 2019. |
| Web of Science Citations: | 1 |
| Abstract | |
The baroreflex is a prominent moment-to-moment mechanism regulating the blood pressure. The hippocampus is a limbic structure in which has been pointed out as part of central network regulating baroreflex. However, the local neurochemical mechanisms involved in control of baroreflex function are not completely understood. Thus, this study aimed to investigate the involvement of nitrergic neurotransmission present in the dorsal hippocampus in baroreflex control of heart rate in conscious rats. For this, we evaluated the effect of bilateral microinjection into the dorsal hippocampus of either the nitric oxide (NO) scavenger carboxy-PTIO, the selective neuronal nitric oxide synthase (nNOS) inhibitor Nw-Propyl-L-arginine (NPLA) or the selective inducible nitric oxide synthase (iNOS) inhibitor 1400 W in bradycardia evoked by blood pressure increases in response to intravenous infusion of phenylephrine, and tachycardia caused by blood pressure decreases evoked by intravenous infusion of sodium nitroprusside. Bilateral microinjection of carboxy-PTIO into the dorsal hippocampus decreased the baroreflex tachycardic response without affecting the reflex bradycardia. Hippocampus treatment with NPLA increased the baroreflex bradycardia gain without affecting the reflex tachycardia. Bilateral hippocampal treatment with 1400 W decreased the reflex tachycardia and increased the baroreflex bradycardic response. Overall, these findings provide evidence that hippocampal nitrergic mechanisms acting in a NOS isoform-specific manner plays a prominent role in control of baroreflex function. Indeed, the results indicate that nNOS and iNOS exerts an inhibitory influence on reflex bradycardia, whereas iNOS mediates the reflex tachycardia. (AU) | |
| FAPESP's process: | 17/19249-0 - Involvement of angiotensinergic neurotransmissions of medial amygdaloid nucleus in control of cardiovascular and anxiogenic responses to stress in rats. |
| Grantee: | Carlos Cesar Crestani |
| Support Opportunities: | Regular Research Grants |
| FAPESP's process: | 15/05922-9 - Study of the participation of CRF neurotransmission in the bed nucleus of the stria terminalis in cardiovascular changes evoked by stress: interaction with the NMDA receptor/nitric oxide / guanilil cycles / protein kinase g signaling pathway? |
| Grantee: | Carlos Cesar Crestani |
| Support Opportunities: | Regular Research Grants |