Reflex increases in heart-rate induced by perfusing the hind leg of the rat with solutions containing lactic acid

Thimm, F.; Carvalho, Marilene; Babka, Martha; Verl, Elisabeth Meier zu

doi:10.1007/bf00581561

Cited by 38 publications

(13 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Hypoxia would be expected to result in impairment of aerobic ATP production by the muscle cell (Idstrom et al 1985;Wolfe et al 1988) and an early rise in sympathetic activity (Seals et al 1991;Warner and Mitchell 1991). Lactate acting at the level of the peripheral circulation may stimulate cardiovascular responses directly and may be an additional factor in the close relationship between the DPBP and the LAT la (Thimm et al 1984;Gregory et al 1987). This latter possibility would be consistent with our finding that the DPBP occurs slightly later than the Th la .…”

Section: Discussionmentioning

confidence: 97%

Association between the anaerobic threshold and the break-point in the double product/work rate relationship

Riley

Maehara

Pórszász

et al. 1996

European Journal of Applied Physiology

View full text Add to dashboard Cite

A break point in the double product versus work rate relationship (DPBP) during incremental exercise has previously been reported. The aim of the current study was to investigate the frequency and degree of inter-observer agreement with which a DPBP could be detected. We also wished to determine its relationship, if any, to the lactic acidosis threshold (LATla). Ten normal volunteers performed continuous incremental bicycle ergometer exercise under three different concentrations of inspired oxygen (FiO2 = 0.21, 0.15 and 0.12). In addition, a group of patients with diseases expected to result in impaired exercise tolerance performed exercise under room air conditions. Gas exchange was measured continuously and double product was measured at 15-s intervals throughout exercise using an automated sphygmomanometer. Four observers, unaware of subject identity and test condition, analysed a total of 39 tests. All four observers detected a DPBP in 29 cases (74%) and an LAT in 35 cases (90%). The intra-class correlation coefficient was 0.76 for the DPBP and 0.93 for the LATla, indicating a reasonable level of agreement among observers for both break points. The DPBP was closely related to the LATla (r = 0.865, P < 0.0001), although it occurred at a slightly higher oxygen consumption (VO2, bias 0.137 1.min-1, 95% confidence intervals 0.041-0.233). We conclude that the DPBP is a common occurrence during incremental exercise. The close relationship between the DPBP and the LATla suggests that both may reflect similar events at the level of the skeletal muscle cell.

show abstract

Section: Discussionmentioning

confidence: 97%

Association between the anaerobic threshold and the break-point in the double product/work rate relationship

Riley

Maehara

Pórszász

et al. 1996

European Journal of Applied Physiology

View full text Add to dashboard Cite

show abstract

“…In this regard, several observations indicate that the stimulation of MSNA evoked by incremental rhythmic handgrip (18) and caused reflex increases in arterial pressure and heart rate (19). In conscious dogs, the arterial pressure response to progressive muscle ischemia during exercise was highly correlated with venous effluent pH (20).…”

Section: Discussionmentioning

confidence: 99%

Sympathetic nerve discharge is coupled to muscle cell pH during exercise in humans.

Victor¹,

Bertocci²,

Pryor³

et al. 1988

J. Clin. Invest.

323

269

View full text Add to dashboard Cite

We used phosphorus nuclear magnetic resonance spectroscopy (31P-NMR) to probe the cellular events in contracting muscle that initiate the reflex stimulation of sympathetic outflow during exercise. In conscious humans, we performed 3"P-NMR on exercising forearm muscle and simultaneously recorded muscle sympathetic nerve activity (MSNA) with microelectrodes in the peroneal nerve to determine if the activation of MSNA is coupled to muscle pH, an index of glycolysis, or to the concentrations (0) of inorganic phosphate (Pi) and adenosine diphosphate (ADP) which are modulators of mitochondrial respiration. During both static and rhythmic handgrip, the onset of sympathetic activation in resting muscle coincided with the development of cellular acidification in active muscle. Furthermore, increases in MSNA were correlated closely with decreases in intracellular pH but dissociated from changes in phosphocreatine (IPCrI), [Pi], and [ADPI. The principal new conclusion is that activation of muscle sympathetic outflow during exercise in humans is coupled to the cellular accumulation of protons in contracting muscle.

show abstract

“…It has been shown that discharge properties of group IV fibres increase during metabolic changes in an exercising muscle 36,37 . Infusion of lactic acid into an isolated perfused rat's hindleg increases HR 38 . In addition, Gregory et al.…”

Section: Discussionmentioning

confidence: 99%

“…36,37 Infusion of lactic acid into an isolated perfused rat's hindleg increases HR. 38 In addition, Gregory et al 39 have shown that injection of lactic acid into the arterial supply of the rat's hindlimb reflexly increases HR, which is not affected by cutting the nerve supply to hindlimb muscles, whereas cutting the nerve supply to the skin abolishes the response. However, Gregory et al 39 state '… perfusion of a hindlimb with l actate solutions is not an adequate technique to identify ergoreceptors in muscle'.…”

Section: Discussionmentioning

confidence: 99%

Cardiovascular Responses During Stimulation Of Hindlimb Skeletal Muscle Nerves In Anaesthetized Rats

Ishide¹,

Pearce²,

Ally³

2002

Clin Exp Pharma Physio

View full text Add to dashboard Cite

1. Cardiovascular responses during static skeletal muscle contraction in anaesthetized rats appear to be contradictory. The present study attempted to explain such variations by stimulating different peripheral nerves supplying the hindlimb skeletal muscles using anaesthetized Sprague-Dawley rats. 2. Muscle contractions were evoked by a 30 s stimulation of the sciatic, tibial, peroneal nerves or the sciatic nerve with transected peroneal branch at threefold the motor threshold, 0.1 msec duration and 40 Hz frequency. 3. Contractions during stimulation of the tibial or the sciatic nerve with severed peroneal branch evoked similar increases in arterial pressure and heart rate. Following stimulation of the tibial nerve, blood pressure, heart rate and muscle tension increased by 23 +/- 3 mmHg, 31 +/- 5 b.p.m. and 789 +/- 34 g, respectively. For the sciatic nerve with transected peroneal branch, increases the respective increases were 27 +/- 5 mmHg, 32 +/- 6 b.p.m. and 802 +/- 43 g. In contrast, peroneal nerve stimulation produced depressor and bradycardic responses of -22 +/- 5 mmHg and -40 +/- 9 b.p.m., respectively. Interestingly, intact sciatic nerve stimulation elicited pressor, depressor or no responses (average being -10 +/- 8 mmHg), along with a consistent increase in heart rate of 24 +/- 7 b.p.m. 4. The results demonstrate that static muscle contraction following stimulation of the tibial or sciatic nerve with transected peroneal branch, elicits consistent increases in blood pressure and heart rate. Furthermore, stimulation of the peroneal nerve elicits a depressor response, while stimulation of the intact sciatic nerve evokes variable cardiovascular responses. Overall, anaesthetized rats can be excellent models to study the variable cardiovascular responses during activation of group III and/or group IV muscle afferents.

show abstract

Reflex increases in heart-rate induced by perfusing the hind leg of the rat with solutions containing lactic acid

Cited by 38 publications

References 24 publications

Association between the anaerobic threshold and the break-point in the double product/work rate relationship

Association between the anaerobic threshold and the break-point in the double product/work rate relationship

Sympathetic nerve discharge is coupled to muscle cell pH during exercise in humans.

Cardiovascular Responses During Stimulation Of Hindlimb Skeletal Muscle Nerves In Anaesthetized Rats

Contact Info

Product

Resources

About