Mechanographic analysis of muscle rigidity after morphine and haloperidol: a new methodological approach

Abstract

The new method described in this study was based on consecutive repeated measurements of the resistance of flexor and extensor muscles of the hind foot of the rat to forced flexions and extensions of the foot. Locomotor movements of the rat were restrained with a metaplex box which had a slot for the hind limb. The control muscle tone measured by this method was constant for more than 2 h, and amounted to approx. 25 g for flexor muscles, and approx. 45 g for extensors. Morphine (2.5, 5, 10, 20 mg/kg) enhanced dose-dependently the resistance of flexor muscles up to approx. 45 g, 70 g, 100 g and 140 g, respectively, and the resistance of extensors of the paw up to approx. 100 g, 140 g, 180 g and 240 g, respectively. Haloperidol (5 and 10 mg/kg) enhanced dose-dependently the resistance of flexor muscles up to approx. 45 g and 70 g, respectively, and that of extensors of the foot up to approx. 75 g and 120 g, respectively. Morphine rigidity, measured as resistance of respective muscles to forced movements, was almost completely inhibited by a consecutive injection of 0.2 mg/kg of naloxone. The new method seems to have considerable advantages in comparison with electromyographical (EMG) or other kinds of mechanographical measurements of the muscle tone.

The role of excitatory amino acids in experimental models of Parkinson's disease

“…A similar effect was obtained by , who used a mechanomyographic method of measuring the muscular rigidity. By this method one can measure the resistance of the rat's hind limb in response to an imposed bending and straightening in the ankle joint (Kolasiewicz et al, 1987). This resistance is accepted as muscular rigidity.…”

The role of reflex activity in the regulation of muscle tone in rats

“…The results presented show that rats respond with increasing resistance to passive flexion or extension of the hindfeet. Our previous experiments demonstrated that such resistance is a reliable measure of muscle tone (Kolasiewicz et al 1987;Ossowska et al 1992Ossowska et al , 1994Wolfarth et al 1992;Lorenc-Koci et al 1994). The maximum resistance (MMGmax) observed in normal, young animals was significantly greater during flexion than during extension (Kolasiewicz et al 1987;Wolfarth et al 1992; present results) presumably because the gastrocnemius muscle (which is stretched during flexion) is larger than the tibialis anterior muscle (which is stretched during extension).…”

“…Our previous experiments demonstrated that such resistance is a reliable measure of muscle tone (Kolasiewicz et al 1987;Ossowska et al 1992Ossowska et al , 1994Wolfarth et al 1992;Lorenc-Koci et al 1994). The maximum resistance (MMGmax) observed in normal, young animals was significantly greater during flexion than during extension (Kolasiewicz et al 1987;Wolfarth et al 1992; present results) presumably because the gastrocnemius muscle (which is stretched during flexion) is larger than the tibialis anterior muscle (which is stretched during extension). The appearance of short-and long-latency components of the reflex EMG activity in response to the stretching of different muscles has been well documented in humans (Marsden et al 1973; Lee & Tatton, 1975;Berardelli et al 1983;Rothwell et al 1983;Tatton et al 1984;Scholz et al 1987;Lee, 1989;Bergui et al 1992; for reviews see Matthews, 1991;Davidoff, 1992) and primates (Lee & Tatton, 1975; for review see Matthews, 1991).…”

“…An increase in muscle tone occurs in numerous neurological diseases, such as Parkinson's disease and Alzheimer's disease, in disorders such as spasticity, and also as a consequence of diverse pharmacological treatments (Rushworth, 1960;Wand, Kuschinsky & Sontag, 1973;Doudet, Gross, Lebrun-Grandie & Bioulac, 1985;Klockgether, Schwarz, Turski, Wolfarth & Sontag, 1985;Huff & Growdon, 1986;Ossowska, Wardas, Warchat, Kolasiewicz & Wolfarth, 1986;Kolasiewicz, Baran & Wolfarth, 1987;Wardas, Ossowska & Wolfarth, 1987;Lee, 1989;Franssen, Reisberg, Kluger, Sinaiko & Boja, 1991;Thilmann, Fellows & Garms, 1991;Benazzouz, Gross, Dupont & Bioulac, 1992;Wolfarth, Kolasiewicz, Ossowska & Bober, 1992;Ibrahim, Berger, Trippel & Dietz, 1993;. Although mucle tone (measured as resistance to passive movement) is routinely examined in humans, the mechanisms underlying changes in muscle tone are still unclear.…”

“…To this end we used a mechanomyographic (MMG) method, developed earlier in our laboratory (Kolasiewicz et al 1987;Ossowska, Schulze, Wolfarth, Coper, Kaminiska & Hausmanowa-Petrusewicz, 1992;Wolfarth et al 1992; Ossowska, Wardas, Konieczny & Wolfarth, 1994;Ossowska et al 1994), which consists of measuring the resistance of the hindlimb to a passive flexion and extension at the ankle joint. Pharmacological studies with drugs that induce muscle rigidity (haloperidol, morphine and reserpine: Kolasiewicz et al 1987;Wolfarth et al 1992;Ossowska et al 1994), or muscle relaxation (diazepam and baclofen: Wolfarth et al 1992;Lorenc-Koci et al 1994) showed that the method is suitable for the examination of muscle tone. In the present study, electromyographic (EMG) recording (Wand et al 1973;Ossowska et al 1986Ossowska et al , 1992Wardas et al 1987) …”