Power spectral analysis of short-term RR interval and arterial blood pressure oscillations in the lizard,Gallotia galloti: Effects of sympathetic blockade
✍ Scribed by De Vera, Luis; Gonz�lez, Juli�n
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 148 KB
- Volume
- 283
- Category
- Article
- ISSN
- 0022-104X
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✦ Synopsis
The role of the sympathetic limb of the autonomic nervous system (ANS) in the mediation of oscillations in consecutive beat-to-beat RR interval (RRI) and systolic blood pressure (SBP) values of lizards, Gallotia galloti, was investigated using spectral analysis and measuring effects of autonomic blockers. α-Adrenergic blockade decreased the power spectral density (PSD) of both RRI and SBP very low frequency (VLF: 0.007-0.055 Hz) and low frequency (LF: 0.055-0.150 Hz) bands, whereas β-adrenergic blockade increased the PSD of both RRI-and SBP-VLF and RRI-and SBP-LF bands. These findings suggest that in lizards 1) the VLF and LF peaks of RRI and SBP power spectra are α-adrenergic mediated, and that 2) the β-adrenergic activity of the sympathetic system may act buffering all RRI and SBP oscillations below 0.150 Hz. These results, when analyzed jointly with the ones obtained from a previous study (De Vera and González. 1997. Comp Biochem Physiol 85A:389-394) on the effects of parasympathetic blockade on lizards' RRI and SBP oscillations, demonstrate that these reptiles, like mammals, exhibit spontaneous short-term oscillations in their HR and SBP which are mediated by the ANS. However, unlike mammals, the RRI and ABP low-frequency oscillations in Gallotia seem to be similarly affected by the ANS and appear to be powered by α-adrenergic and parasympathetic activities and buffered by β-adrenergic activity.