Pain Laboratory

Research Laboratories

Pain Laboratory
Incharge- Prof. R.Mathur

The research activities in the Pain Laboratory, Department of Physiology revolve around the central mechanism of pain modulation. The laboratory is equipped with the state of art equipment for electrophysiological, neuro-chemical and behavioural studies, which have been funded by the Institute, DST, ICMR and CSIR.

The group has significantly contributed towards the following:

· The role of postnatal nutrition on the functional maturity of hypothalamus:

We were the first to provide the ontogeny calendar for various controls exerted on feeding behaviour and thereby on body weight of the adults. Protein-calorie undernutrition or carbohydrate overload during development influences the ontogeny of hypothalamic feeding centers, which dictate eating behaviour and body weight of the adult. The critical period for the development of these centers is the initiation of weaning and is governed by the biochemical cues.

· The role of various neural sites involved in pain modulation:

a) We have provided sufficient comparative data to demonstrate involvement of hippocampus, cingulate gyrus, amygdala, septum and hypothalamus in the modulation of pain. We are the first to demonstrate that each area has its special unique feature of the control. For example activation of ventromedial hypothalamus reduces pain via its glucoresponsive neurons in relation to the food such as ingestion of palatable food.

b) Palatable food ingestion relieves moderately chronic severe repetitive stress of unpredictable type interval and intensity.

We designed a test namely sucrose challenge test utilizing the above-mentioned observations to determine the pain status of an individual. It is cheap, economical, safe, quick and a sensitive tool in the hands of a scientist as well as clinician. We have utilized this test to:

i) Differentiate early cases of Alzheimer Disease patients from dementia of
other causes;

ii) Demonstrate greater efficacy of yogic life style intervention than use of

NSAIDS or BOTOX in Chronic Tension type headache.

iii) Demonstrate efficacy of ganglion block in Trigeminal neuralgia patients.

· Bio-interaction of magnetic fields:

We have reported the mechanism underlying attenuation of pain, relief of stress and deficit in memory produced by intermittent chronic exposure to magnetic fields.

· The role of prenatal auditory stimulation on the auditory preference, learning and memory and stress:

We have developed a chick model to study the effects of prenatal auditory stimulation. The learning is enhanced at a younger age in chicks receiving prenatal auditory stimulation.

Recent Research Project undertaken

Motor responses to noxious/non-noxious stimuli in spinalised humans and rats : Role of electromagnetic stimulation in recovery: Indo-Russian Project

Spinal injury de-links the motor cortex, spinal central pattern generators (CPGs) and peripheral receptors. Besides, it also provides a hostile biochemical and cellular micro-environment for recovery in terms of biochemical and cellular profiles.

We study the pattern of recovery in both the sensory and motor functions after embryonic stem cells transplantation locally, magnetic stimulation of motor cortex and spinal cord and peripheral sensory stimulation with a view to re-establish the loop of information flow from motor cortex to spinal cord, periphery to spinal cord and vice-versa.

Our Select publications

BOOK - Pain Updated: Mechanisms and Effects

Editor : Rashmi Mathur

1. Mathur RK, Mukherjee K, Mathur R. Threshold of pain in chronic magnetic field (50 Hz, 17.9 mT) exposed rats :Effect of sucrose ingestion. Electromagnetic Biology and Medicine (In press).

2. Jain S, Sharma R, Wadhwa S. Effect of prenatal species-specific and music stimulation on the postnatal auditory preference of the domestic chick. Indian Journal Physiology Pharmacology 48(2): 174-183, 2004.

3. Jain S, Mathur R, Sharma R, Nayar U. Recovery from lesion-learning deficits by fetal amygdala transplants. Neural Plasticity 9(1): 53-63, 2002.

4. Mukherjee K, Mathur R, Nayar U. Hyperalgesic response in rats fed sucrose from weaning to adulthood: Role of VMH. Pharmacology Biochemistry Behaviour 73(3): 601-610, 2002.

5. Mukherjee K, Mathur R, Nayar U. Ventromedial hypothalamic mediation of sucrose feeding induced pain modulation. Pharmacology Biochemistry Behaviour 68: 43-48, 2001.

6. Mukherjee K, Mathur R, Nayar U. Nociceptive response to chronic stress of restraint and noxious stimuli in sucrose fed rats. Stress and Health 17: 297-305, 2001.

7. Dutta R, Mukherjee K, Mathur R. Effect of VMH lesion on sucrose fed analgesia in formalin pain. Japanese Journal of Physiology 51(1): 63-69, 2001.

8. Mukherjee K, Mathur R, Nayar U. Effect of VMH lesion of sucrose fed nociceptive responses. Japanese Journal of Physiology 50 (4): 395-404, 2000.

9. Jain S, Mathur R, Sharma R, Nayar U. Amygdalar tissue transplants improve recovery of nociceptive behaviour in rats. Restorative Neurology and Neuroscience 16(2): 143-147: 2000.

10. Jain S, Mathur R, Sharma R, Nayar U. Neural tissue transplant in the lateral hypothalamic lesioned rats: Functional recovery pattern. Neurobiology 7(4): 421-430, 1999.

11. Aggarwal P, Kharbanda OP, Mathur R, Duggal R, Prakash H. Muscle response to the twin-block appliance : An electromyographic study of the masseter and anterior temporal muscles. American Journal of Orthodontics and Dentofacial Orthopedics 116(4): 405-414, 1999.

12. Kulkarni SK, Geroge B, Mathur R. Protective effect of Withania Somnifera root extract on electrographic activity in a lithium-pilocarpine model of status epilepticus. Phytotherapy Research 12: 451-453, 1998.

13. Mathur R, Nayar U, Manchanda SK. Body weight at onset of weaning determines weight at maturity. Developmental Brain Dysfunction 9(1) : 1-8, 1996.

14. Mathur R, Manchanda SK, Oomura Y, Nayar U. 2-Buten 4 Olide affects feeding behaviour of rhesus monkey. Progress in Neuro-Psychopharmacology and Biological Psychiatry 20 (1): 167-176,1996.

15. Mathur R, Manchanda SK. Ontogeny of phenylalanine (Endogenous cholecystokinin) induced modulation of food intake in normal and malnourished rats. Progress in Neuro-Psychopharmacology and Biological Psychiatry 15: 405-413,1991.

16. Mathur R, Nayar U, Manchanda SK. Ontogeny of hypothalamic glucostatic feeding mechanism in developing rats, J. of Bioelectricity 5(2): 343-351, 1986.