Bioassay of oxytocin

Bioassay of Oxytocin

1. Presented by Trisha Das M Pharm 1 st Semester/Year Advanced Pharmaceutical Analysis Pharmaceutical Analysis & Quality Assurance BIOASSAY OF OXYTOCIN

2. Oxytocin Oxytocin is a peptide hormones and Neuropeptide. Oxytocin is normally produced by the paraventicular nucleus of the hypothalamus and released by the posterior pituitary.

3. Role of Oxytocin Oxytocin is a natural hormone that causes the uterus to contract. Oxytocin is used to induce labor or strengthen labor contractions during childbirth, and to control bleeding after childbirth. Oxytocin is also used to stimulate uterine contractions in a woman with an incomplete or threatened miscarriage.

4. Bioassay of O xytocin The potency of oxytocin injection is determined by comparing its activity with that of the standard preparation of  oxytocin under the conditions of the following method of assay.

5. Standard Preparation and Unit: The standard preparation is a freeze dried preparation of oxytocin with albumin and citric or any other suitable preparation, the potency of which had been determined in relation to the International standard The Unit is the specific oxytocin activity corresponding to that yielded by 0.0005 g of  the Standard preparation .

6. EXTRACT OF STANDARD PREPARATION THE DRY POWDER (20 UNITS ) WEIGHED WASHED TUBE IS PLACED IN BOILING WATER COOLED FILTERED FILTRATE (2 UNITS/ml )

7. Method Test animals Use female rats in dioestrous, weighing between 120 and 200 g anoestrus female guinea pigs weighing between 175 g and 350 g.

8. Method of cmparison By contraction of the rat uterus Inject   100 microgram of oestradiol intramuscularly. Kill the rat and suspend one horn of the uterus in a bath containing Locke ringers solution. Maintain the bath at a temperature of 32º.

9. Oxygenate the solution. Record the contractions produced by the addition to the both of two doses of the Standard Preparation suitably diluted with the above solution . The doses should be such as to produce clearly discriminated contractions.

10. The required doses : Between 10 and 50micro Units per ml. When maximal contraction has  replace the bath liquid by a fresh reached solution. The doses should be added at regular intervals of 3 to 5 minutes.

11. Dilute the preparation under examination so as to obtain responses on the addition of two doses similar to those obtained with the Standard The ratio between the two doses  of the preparation under examination should be the same as that between the two doses of the Standard Preparation and this ratio should kept constant throughout the assay

12. Prepare The two doses of  Standard and the two doses of the test should  be and given in a random order and at least six responses to each should be measured. Measure all the responses and the result of the assay by standard statistical methods .  

13. Reference ttps:// www.scribd.com/doc/28887077/Oxytocin-bioassay https://joe.bioscientifica.com/view/journals/joe/29/3/joe_29_3_009.xml