Table 5.
Responses to activation of cardiopulmonary reflexes (i.v. phenylbiguanide, PBG) and central baroreflex pathways (microinjection of NTS l-glu) (Protocol 3)
Control | After RVLM GX+S | |||||
---|---|---|---|---|---|---|
Δ MAP (mm Hg) | Δ RSNA (% i/sec) | Δ RSNA (% RMS) | Δ MAP (mm Hg) | Δ RSNA (% i/sec) | Δ RSNA (% RMS) | |
PBG | −33.9 ± 7.2 | −59.3 ± 10.1 | −82.8 ± 4.4 | −2.7 ± 4.0* | 4.6 ± 5.3* | 5.1± 4.2* |
NTS l-glu | −35 ± 4.0 | −51.9 ± 10.9 | −74.4± 6.9 | 0.4 ± 3.9* | 6.5 ± 3.3* | −6.9 ± 3.5* |
At the beginning of the protocol (Control), both PBG and unilateral microinjection of l-glu into the NTS resulted in significant decreases in MAP and RSNA. Bilateral blockade of GABAA, GABAB, and glycine receptors (GX + S) in the RVLM eliminated reflex responses. Values = mean ± SEM;
P ≤ 0.05 compared to corresponding control value.