The ultrastructure of muscle fibres, membrane electrical constants and synaptic membrane responses to microapplication of l-glutamate were investigated in longitudinal flight muscle and flexor tibia of Locusta migratoria migratorioides. The sarcomers of the flight muscle (fast) were smaller then those of the leg muscle (slow). The effective resistances (Ro) of the flight and leg muscles were (2.25 +/- 0.54)-10(5) omega and (1.65 +/- 0.57) X 10(5) omega. The specific resistance (Rm), space constant (tau) and time constant (lambda) in the same muscles were 774 +/- 106 omega-cm and 2583 +/- 119 omega-cm-2; 7.3 +/- 1.7 ms and 17.5 +/- 1.1 ms; 093 +/- 0.22 mm and 1.98 +/- 0.42 mm. When l-glutamate was applied iontophoretically to muscle fibres depolarization was recorded only in localized parts of the membrane. Microapplication of acetylcholine to intact and denervated muscle fibres of the slow leg muscle was uneffective. It is suggested that l-glutamic acid is the excitatory transmitter both in slow and fast insect muscles.

Download full-text PDF

Source

Publication Analysis

Top Keywords

muscle fibres
12
flight muscle
8
leg muscle
8
+/-
8
muscle
7
[functional features
4
features locomotor
4
muscles
4
locomotor muscles
4
muscles locust]
4

Similar Publications

Background: Normothermic ex situ heart perfusion (ESHP) has emerged as a valid modality for advanced cardiac allograft preservation and conditioning prior to transplantation though myocardial function declines gradually during ESHP thus limiting its potential for expanding the donor pool. Recently, the utilization of dialysis has been shown to preserve myocardial and coronary vasomotor function. Herein, we sought to determine the changes in myocardial metabolism that could support this improvement.

View Article and Find Full Text PDF

An optogenetic mouse model of hindlimb spasticity after spinal cord injury.

Exp Neurol

January 2025

Brain and Mind Research Institute, Department of Biology, University of Ottawa, Ottawa, Ontario, Canada. Electronic address:

Spasticity is a common comorbidity of spinal cord injury (SCI), disrupting motor function and resulting in significant discomfort. While elements of post-SCI spasticity can be assessed using pre-clinical SCI models, the robust measurement of spasticity severity can be difficult due to its periodic and spontaneous appearance. Electrical stimulation of sensory afferents can elicit spasticity-associated motor responses, such as spasms; however, placing surface electrodes on the hindlimbs of awake animals can induce stress or encumbrance that could influence the expression of behaviour.

View Article and Find Full Text PDF

Gentisic acid protects Sprague-Dawley rats from myocardial infarction through reversing electrocardiographical, biochemical and histopathological abnormalities.

Biochem Biophys Res Commun

January 2025

Cardiovascular Research Group, Department of Pharmacy, COMSATS University Islamabad, Abbottabad Campus, University Road, Tobe Camp, Abbottabad, 22060, KPK, Pakistan. Electronic address:

Gentisic acid (GA), a cytochrome P450 metabolite of the antiplatelet drug aspirin, exhibits smooth muscle relaxant, antiatherogenic, and antioxidant activities. It also has a protective role in hypertrophic heart failure, suggesting its role in the management of myocardial infarction (MI). This study aimed to explore the protective activity of GA in isoproterenol (ISO)-induced MI in Sprague-Dawley (SD) rats in-vivo, followed by mechanistic investigation ex-vivo.

View Article and Find Full Text PDF

Background: This is a novel rat study using native peptide therapy, focused on reversing quadriceps muscle-to-bone detachment to reattachment and stable gastric pentadecapeptide BPC 157 per-oral therapy for shared muscle healing and function restoration.

Methods: Pharmacotherapy recovering various muscle, tendon, ligament, and bone lesions, and severed junctions (i.e.

View Article and Find Full Text PDF

This study investigates the effects of electrical stimulation (EMS) combined with strength training on lower limb muscle activation and badminton jump performance, specifically during the "jump smash" movement. A total of 25 male badminton players, with a minimum of three years of professional training experience and no history of lower limb injuries, participated in the study. Participants underwent three distinct conditions: baseline testing, strength training, and EMS combined with strength training.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!