Pinch Test Research Articles

A blind controlled trial of adrenocorticotropin and cerebral gangliosides in nerve regeneration in the rat

Rapid axonal regeneration and successful reinnervation of muscle and sensory end organs are the requisites for effective recovery from nerve lesions. Axonal regeneration has been reportedly accelerated by cerebral gangliosides and ACTH. We measured the rate of regeneration of sensory axons in rats after sciatic nerve crush by using the pinch test. We found no difference between rats treated with ACTH or gangliosides and the control group.

Analgesia following microinjection of phosphodiesterase inhibitors at brainstem sites

Microinjection of RO 20-1724 (0.60 μg) at sites in the caudal reticular formation of the rat brainstem resulted an analgesia in the tail flick, paw pinch and hot plate tests. Microinjection of theophylline (0.45 μg) at sites in the caudal reticular formation also produced analgesia in the tail flick and hot plate tests, but not in the paw pinch test. Since these agents inhibit phosphodiesterase and elevate cyclic nucleotides in rat brain homogenates, these data suggest that cyclic nucleotides have a functional role in brainstem structures involved in modulation of nociceptive threshold.

Isolation and identification of an analgesic opioid dipeptide kyotorphin (TYR-ARG) from bovine brain

A novel opioid analgesic peptide termed “Kyotorphin” was isolated and identified from bovine brain, using an in vivo analgesia assay method. The analgesic activity was assessed by a combination of intracisternal injection and the tail pinch test in mice. The sequence of this peptide was determined as Tyr-Arg by amino acid analysis and the N-terminal determination by the dansylation method. The natural peptide was confirmed to be identical to the synthetic peptide on TLC, HVPE and HPLC. The median analgesic dose, ED 50 of kyotorphin was 34.7 nmol/mouse with the tail pinch test and the potency was 4.2 times greater than that of met-enkephalin. With the hot plate test, the ED 50 of kyotorphin was 15.7 nmol/mouse and this effect was completely reversed by the pretreatment with naloxone (0.1 mg/kg, s.c.). The present analgesic assay method can thus be effectively applied to endogenous opioid substances to establish analgesic actions.

Effect of 1,1-diphenyl-3-piperidinobutanol hydrochloride (Aspaminol) on the stimuli-induced calcium uptake in rat brain synaptosomes.

Effects of 1,1-diphenyl-3-piperidinobutanol hydrochloride (Aspaminol), a nonspecific smooth muscle relaxant, on the uptake of calcium in the synaptosomes of rat brain were studied, using two stimuli i.e. high KCl and ATP. We also studied the effect of Aspaminol on the analgesic response of rat hindpaw using the Randall-Sellito test. The addition of Aspaminol inhibited the stimuli-induced calcium uptake in a concentration dependent manner. Aspaminol inhibited the high KCl induced calcium uptake competitively against the external calcium concentration. These findings suggest that Aspaminol may act on the surface of the synaptosomal membranes. In case of ATP stimulated calcium uptake, Aspaminol reduced the rate of uptake and maximal level of the synaptosomal calcium, and did not appear to have any effect on the rate of calcium release. These findings suggest that the inhibitory effect of Aspaminol can be mainly attributed to inhibition of the calcium influx, but not to acceleration of calcium efflux. In the five weeks old rats, Aspaminol did not influence the responses in the paw pinch test, but, in the weanling rats (about three weeks old). Aspaminol had a slight effect on the responses in the paw pinch test. This discrepancy may be due to difficulties in passing through the blood-brain barrier. Our findings suggest that a certain relationship may exist between the analgesic effect and the calcium uptake in the synaptosomes.

EFFECT OF 1,1-DIPHENYL-3-PIPERIDINOBUTANOL HYDROCHLORIDE (ASPAMINOL) ON THE STIMULI-INDUCED CALCIUM UPTAKE IN RAT BRAIN SYNAPTOSOMES

AbstractEffects of 1,1 -diphenyl-3-piperidinobutanol hydrochloride (Aspaminol), a nonspecific smooth muscle relaxant, on the uptake of calcium in the synaptosomes of rat brain were studied, using two stimuli i.e. high KCl and ATP. We also studied the effect of Aspaminol on the analgesic response of rat hindpaw using the Randall-Sellito test. The addition of Aspaminol inhibited the stimuli-induced calcium uptake in a concentration dependent manner. Aspaminol inhibited the high KCl induced calcium uptake competitively against the external calcium concentration. These findings suggest that Aspaminol may act on the surface of the synaptosomal membranes. In case of ATP stimulated calcium uptake, Aspaminol reduced the rate of uptake and maximal level of the synaptosomal calcium, and did not appear to have any effect on the rate of calcium release. These findings suggest that the inhibitory effect of Aspaminol can be mainly attributed to inhibition of the calcium influx, but not to acceleration of calcium efflux. In the five weeks old rats, Aspaminol did not influence the responses in the paw pinch test, but, in the weanling rats (about three weeks old), Aspaminol had a slight effect on the responses in the paw pinch test. This discrepancy may be due to difficulties in passing through the blood-brain barrier. Our findings suggest that a certain relationship may exist between the analgesic effect and the calcium uptake in the synaptosomes.

Rate of regeneration of sensory axons in transected rat sciatic nerve repaired with epineurial sutures

Rat sciatic nerves were cut and the ends were rejoined using epineurial sutures. The most rapidly regenerating sensory axons, as measured by the pinch test, grew at a rate of 3.2 ± 0.2 (SE) mm/day after a delay of 4.0 ± 0.3 (SE) days. Regenerating axons began to grow beyond the site of injury about 2 days later in sutured nerves than in crushed nerves; this difference provides an estimate of the scar delay in sutured nerves. The rate of axonal outgrowth was slower in sutured nerves than in crushed nerves throughout the distal stump.

Comparison of the analgesic effects of various opioid peptides by a newly devised intracisternal injection technique in conscious mice

To determine accurately the central analgesic effects of opioid peptides, we devised a special technique for intracisternal administration of drugs to conscious mice. When this method was utilized we found that a series of endogenous opioid peptides and enkephalin analogues, (D-Ala 2, Met 5)-enkephalinamide and (D-Met 2,Pro 5)-enkephalinamide produced dose-related analgesic effects, as determined by the tail pinch test. These effects were antagonized by pretreatment with naloxone 0.5 mg/kg s.c. This technique should be a most accurate one for the determination of central analgesic effects of various drugs in conscious mice.

Cystic fibrosis, atopy, and airways lability.

In a survey of cystic fibrosis (CF) in the Avon area, 48 children with CF from 40 families together with 71 of their parents were studied by spirometry, exercise tests, and pinch tests. A control group of 42 young adults was similarly tested; control data for children were taken from previously published work. The prevalence of atopy (any positive prick test) in children with CF was 48%. Sensitivity to grass pollens and house dust mite was no more common in these children (29%) than in a normal population (34%). Hypersensitivity to Aspergillus fumigatus was found in 35% of children with CF and was associated with severe lung disease. The parents had a normal pattern and prevalence of atopy. Exercise-induced airways obstruction was present in only 22% of children with CF; its association with severe lung disease rendered interpretation difficult. The parents had a normal response to exercise. Both hypersensitivity to A. fumigatus and exercise-induced airways lability had the features of acquired characteristics. There was nothing in the present study to support the hypothesis that the possession of a CF gene predisposed to atopy.

Regeneration of motor axons in the rat sciatic nerve studied by labeling with axonally transported radioactive proteins

Labeling regenerating axons with axonally transported radioactive proteins provides information about the location of the entire range of axons from the fastest growing ones to those which are trapped in the scar. We have used this technique to study the regeneration of motor axons in the rat sciatic nerve after a crush lesion. From 2 to 14 days after the crush the lumbar spinal cord was exposed by laminectomy and multiple injections of [3H]proline were made stereotactically in the ventral horn. Twenty-four hours later the nerves were removed and the distribution of radioactivity along the nerve was measured by liquid scintillation counting. There was a peak of radioactivity in the regenerating axons distal to the crush due to an accumulation of label in the tips of these axons. After a delay of 3.2 +/- 0.2 (S.E.) days, this peak advanced down the nerve at a rate of 3.0 +/- 0.1 (S.E.) mm/day. The leading edge of this peak, which marks the location of the endings of the most rapidly growing labeled fibers, moved down the nerve at a rate of 4.4 +/- 0.2 mm/day after a delay of 2.1 +/- 0.2 days; this is the same time course as that of the most rapidly regenerating sensory axons in the rat sciatic nerve, measured by the pinch test. Another peak of radioactivity at the crush site, presumed to represent the ends of unregenerated axons or misdirected sprouts, declined rapidly during the first week, and more slowly thereafter.

Analgesia produced by direct injection of morphine into the mesencephalic reticular formation

HAIGLER, H. J. AND R. S. MITTLEMAN. Analgesia produced by direct injection of morphine into the mesencephalic reticular formation. BRAIN RES. BULL. 3(6) 655–662, 1978.—Morphine administered intracerebrally (IC) (10 μg as the base on each side) into the MRF produced a significant dose dependent elevation of nociceptive threshold (i.e., analgesia) on the tail flick test and hemostat pinch test. However, morphine IC at lower doses had no analgesic effect. After morphine was injected IC (10 μg, bilaterally) into the MRF, naloxone, a specific narcotic antagonist, administered either IC at the same site (15 μg, bilaterally) or subcutaneously (10 mg/kg), antagonized the antinociceptive effects of morphine. Thirty percent of the animals given bilateral microinjection of 10 μg of morphine displayed hyperreactivity to mild stimuli. This hyperreactivity was not attenuated by large IC or systemic doses of naloxone. It was concluded that the MRF is a site where morphine may act to produce analgesia by a specific narcotic mechanism of action.

Analgesia from rostral brain stem stimulation in the rat

Rats implanted with bipolar stimulating electrodes in the rostral medial brain stem were tested for brain stimulation-produced analgesia using tail-flick, pinch and hot-plate tests. Potent analgesia across all three tests was obtained from stimulation of sites in the gray matter surrounding the aqueduct and the caudal portion of the third ventricle, the posterior hypothalamus, the midline area of the caudal thalamus and the pretectal region of the meso-diencephalic junction. The analgesia obtained from these sites was comparable to that produced by stimulation of the previously studied caudal periaqueductal gray matter: it outlasted the period of brain stimulation, was not due to a generalized motor debilitation of the animal, and was not correlated with changes in electrographic activity. Stimulation of sites in the caudal thalamus and pretectal area yielded analgesia without stimulation-induced aversive reactions, confirming the potential of these sites for use in the relief of clinical pain in man.

Recovery of peripheral nerve function after axotomy: Effect of triiodothyronine

The rate of recovery of motor function after crushing the sciatic nerve was measured in rats treated with daily intraperitoneal injections of 3,3′,5-triiodo- l-thyronine, 25 μg/kg. The nerve was crushed at one of four levels, and recovery of motor function was indicated by the return of toe spreading elicited as part of the vestibular placing response. The rate of recovery was calculated from the linear regression of the time to recovery on the distance from the lesion to the entry of the peroneal nerve into the anterior tibial muscle. The recovery rate of the triiodothyronine-treated group was 4.08 ± 0.22 ( se) mm/day, an increase of 22% from the rate of 3.35 ± 0.14 mm/day ( P = 0.006) in the vehicle-injected control rats. The latent periods for the two groups were not significantly different. The outgrowth of the most rapidly growing sensory axons was measured using the “pinch test” on the 7th or 9th day after sciatic crush in animals treated with triiodothyronine in dosages from 1 to 400 μg/kg/day and compared with control animals. No significant difference in distance regenerated or rate of regeneration was found. Control nerves regenerated at a rate of 4.5 ± 0.15 mm/day after a delay of 2.0 ± 0.2 days. A significant degree of hyperthyroidism was documented by measurements of plasma triiodothyronine concentrations taken 4 and 18 h after the injection of the hormone, 25 μg/kg. At the same dosage animals gained weight normally and showed no signs of thyrotoxicity. These results are interpreted as showing that the accelerated recovery of motor function in the hyperthyroid rat is mediated via an effect on the maturation of the regenerated axon rather than on axonal outgrowth. A triiodothyronine-related increase in the rate of myelination would be consistent with the observed results.

Axonal regeneration in the rat sciatic nerve: Effect of a conditioning lesion and of dbcAMP

After the sciatic nerve had been crushed at the level of the mid-thigh, the rate of outgrowth of the regenerating axons was measured by using the pinch test to locate the leading sensory axons. This standard crush lesion (“testing” lesion) elicited axonal outgrowth at a rate of 4.3 ± 0.1mm/day, with an initial delay (before the axons entered the degenerating distal stump) of 1.6 days. A “conditioning” lesion (transection of the tibial nerve at the ankle), made two weeks before the testing lesion, caused an increase of 23% in the outgrowth rate ( P < 0.02), with no appreciable change in the initial delay. Dibutyryl cyclic AMP (dbcAmP) was found to have no effect on the rate of axonal outgrowth measured by the pinch test. Histological examination of the pinch-tested nerves showed that the drug also had no effect on the numbers of regenerating silver-stained axons or fluorescent noradrenergic axons seen at various levels distal to the testing lesion.

A comparison of clindamycin and penicillin V in the treatment of oral infections

To evaluate the long-term clinical and radiographic outcomes of trapeziectomy with abductor pollicis longus tendon interposition arthroplasty for moderate to severe osteoarthritis of the thumb carpometacarpal joint (Eaton stages III-IV).We evaluated 13 patients (15 thumbs) who underwent trapeziectomy and abductor pollicis longus tendon interposition arthroplasty for end-stage osteoarthritis of the thumb carpometacarpal joint, at an average follow-up of 15 years. Subjective clinical outcomes evaluated included visual analogue scale scores and disability of arm shoulder and hand score questionnaires. Objective clinical evaluation included lateral pinch and grip tests, and a range of active and passive thumb movements. All patients underwent a radiological assessment by two independent senior radiologists. Wherever possible, results obtained from the operated thumbs were compared to the non-operated side.At a mean of 15 years post operation (range 15–17 years), there was no statistical difference between the operated and non-operated hands with regards to grip and pinch strength. In all cases CMC and MCPJ range of motion in the operative hand was either equal to or greater than non-operative counterparts. Mean visual analogue scale score was 2.13 and mean DASH score was 16.85. Mean carpal height was 0.52 and mean trapezial space ratio was 0.163. There were no early or late complications recorded and no revision surgery was required.It is the opinion of these authors that abductor pollicis longus tendon interposition arthroplasty is able to provide high-quality long-term results for patients who suffer from moderate to severe osteoarthritis of the thumb carpometacarpal joint.Therapeutic Level IV.

The synthesis and pharmacology of a new analgesic, ID-1229.

A new non-narcotic analgesic, 2-[3-(p-fluorobenzoyl)-n-propy]-5alpha,9alpha-dimethyl-2'-hydroxy-6,7-benzomorphan (ID-1229) has been prepared from 5alpha,9alpha-dimethyl-2'-hydroxy-6,7-benzomorphan. The analgesic activities of ID-1229 were several times more potent than those of pentazocine in the acetic acid writhing test in mice, bradykinin test in rats, Randall-Selitto's test in rats, and the electrical stimulation test in mice, while, ID-1229 showed little activity in both the tail pinch test and the hot plate test. ID-1229 did not show anti-narcotic activity in the morphine-combined test, and the Straub tail phenomenon was not observed in ID-1229. ID-1229 showed CNS activities in some tranquilizing tests, but did not show activity in several other CNS tests. The CNS potency is condiserably weaker as compared with haloperidol or diazepam, and the pattern of CNS activities in ID-1229 is quite different from those of both compounds. ID-1229 is a potent non-narcotic analgesic with tranquilizing activity, which is quite free from the undersirable side effects of morphine or morphine-like compounds including pentazocine.

Effect of training on the analgesic action of morphine

Groups of mice injected with saline were tested at regular intervals using the hot plate or the tail pinch procedures for measuring analgesia. In the tail pinch test, a decreased analgesic response to an injection of morphine was observed in mice subjected to repeated stimuli as compared to mice receiving a single stimulus. No statistical differences were observed between groups of mice receiving either single or repeated stimuli when analgesia was assessed by the hot plate method. When stimuli were repeated under pentobarbital or a muscle relaxant at dose levels that abolished response to the tail pinch, the effect of a subsequent dose of morphine was comparable to that obtained in mice receiving only a single stimulus.

Is handgrip strength and key pinch measurement related with biochemical parameters of nutrition in peritoneal dialysis patients?

Backgrounds & Objective:End-stage renal disease (ESRD) frequently causes Protein Energy Wasting (PEW), which is an important morbidity and mortality factor. Although it is difficult to assess PEW with a reliable method, there are various methods such as Handgrip strength test (HST), serum albumin, cholesterol, etc. HST is a simple and reliable antropometric method which is used for nutritional status and body muscle strength. This study aims to assess the relationship between HST and biochemical markers in evolution of nutritional status of ESRD patients.Methods:This cross-sectional study included 36 consecutive patients, who are on peritoneal dialysis and 36 healthy –control subjects. Jamar-hand dynamometer was used for handgrip strength test; a pinch gauge was used for key pinch. Other antropometric tests included skin fold thicknesses at biceps, triceps, umbilical, suprailiac and subscapular regions; circumferences at waist hip, neck and midarm. Biochemical tests were performed only in Peritoneal Dialysis (PD) group. SPSS for Windows ver. 15.0 was used for statistics.Results:The mean age of patients was 49.3±14.4, and mean age of control group was 43.8±10.6 (p=0.075). In PD group dominant hand dynamometer test 1,2 and 3 results were 19.3±9.3 kg, 25.3±10.8 kg, 25.5± 10.6 kg and; 34.2±10.3 kg, 34.4±9.8 kg, 34.6±10.0 kg for control group (p< 0,001). Right key pinch results were 6.7±1.9 kg for patients; 13.5±4.5 kg for control group (p<0.001). Left key pinch results were 6.8±1.9 kg for patients; 13.2±4.4 kg for control group (p<0.001). There was not any significant relationship concerning handgrip or key pinch tests with biochemical parameters.Conclusion:Handgrip Strength Test and key pinch may be reliable, cheap and easily performed tests for the diagnosis of Protein Energy Wasting in patients on Peritoneal Dialysis.