Related Experiment Video

Updated: May 28, 2026

Bladder Smooth Muscle Strip Contractility as a Method to Evaluate Lower Urinary Tract Pharmacology
10:26

Bladder Smooth Muscle Strip Contractility as a Method to Evaluate Lower Urinary Tract Pharmacology

Published on: August 18, 2014

Spasmogenic and spasmolytic activities of Onosma griffithii Vatke

Niaz Ali1, Bashir Ahmad, Syed Wadood Ali Shah

  • 1Institute of Basic Medical Sciences, Khyber Medical University, KPK, Peshawar, Pakistan.

Pakistan Journal of Pharmaceutical Sciences
|October 1, 2011
PubMed

Related Concept Videos

Spasmolytic Agents: Chemical Classification01:29

Spasmolytic Agents: Chemical Classification

Spasmolytic agents are drugs used to alleviate muscle spasms and spasticity. They can be categorized into different chemical groups based on their mechanisms of action. Centrally acting spasmolytics primarily affect the spinal cord, while others directly target skeletal muscle cells.
A major class of centrally acting spasmolytics is the α2-agonist, such as tizanidine. These drugs bind to α2-adrenoceptors, inhibiting the release of the excitatory neurotransmitter glutamate. They also promote...
Classification of Skeletal Muscle Relaxants01:28

Classification of Skeletal Muscle Relaxants

Skeletal muscle relaxants are a group of drugs that can reduce muscle stiffness and induce temporary paralysis to relieve pain. These agents can act centrally to reduce muscle tone or spasms in painful conditions such as multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), or spinal injuries; they are called antispasmodics or spasmolytics.
Peripherally acting skeletal muscle relaxants interfere with the neurotransmission at the neuromuscular end plate to induce paralysis during...
Centrally Acting Muscle Relaxants: Therapeutic Uses01:24

Centrally Acting Muscle Relaxants: Therapeutic Uses

Centrally acting muscle relaxants reduce muscle tone and tension by interfering with the postsynaptic reflexes in the central nervous system.
Centrally acting drugs are classified into spasmolytic and antispasmodic drugs. Spasmolytic drugs such as baclofen, diazepam, and tizanidine inhibit spinal motor neurons and decrease muscle tone. Spasmolytic drugs are administered for severe and chronic spasms due to multiple sclerosis, cerebral palsy, stroke, and spinal cord and muscle injuries. However,...
Peripherally and Centrally Acting Muscle Relaxants: A Comparison01:09

Peripherally and Centrally Acting Muscle Relaxants: A Comparison

Skeletal muscle relaxants can target the central nervous system [CNS] to reduce muscle tension or act directly at the neuromuscular junction to induce temporary paralysis. These two classes of muscle relaxants are called centrally acting muscle relaxants and peripherally acting muscle relaxants. They differ in their action, mechanism, administration route, and clinical uses.
Centrally acting muscle relaxants can be further divided into spasmolytic and antispasmodic drugs. Spasmolytic drugs,...
Directly Acting Muscle Relaxants: Dantrolene and Botulinum Toxin01:26

Directly Acting Muscle Relaxants: Dantrolene and Botulinum Toxin

Directly acting muscle relaxants like dantrolene and botulinum toxin (BoNT) have distinct mechanisms and applications. Dantrolene, a hydantoin derivative, acts on the ryanodine receptor (RYR1) in skeletal muscle cells. RYR1 are calcium channels present at the sarcoplasmic reticulum membrane. In response to excitation, they release calcium ions from the sarcoplasmic reticulum to the cytosol. Calcium promotes actin-myosin-mediated contraction of muscles.
The binding of dantrolene to the RYR1...
Skeletal Muscle Relaxants: Therapeutic Uses01:31

Skeletal Muscle Relaxants: Therapeutic Uses

Skeletal muscle relaxants are used to relax muscle tone and alleviate painful muscle contractions. However, the choice of skeletal muscle relaxants depends on the duration of the surgical procedure in order to minimize potential side effects. Skeletal muscle relaxants like neuromuscular blocking agents [NMBAs] are commonly employed as adjuvants alongside general anesthetics in clinical settings. NMBAs are also used to maintain controlled ventilation during surgery of the larynx or pharynx as...