4 votes

what is meta-sympathetic nervous system?

As @mgkrebbs says, metasympathetic nervous system is still a matter of debate and is not fully accepted in the scientific world due to lack of research and evidence. Metasympathetic nervous system, ...
user avatar
4 votes
Accepted

Can stress and arousal be independent?

Stress response has 2 main components: Quick response, within minutes, is by the Sympathomedullary Pathway (SAM): hypothalamus > sympathetic nervous system > release of adrenaline and noradrenaline ...
user avatar
  • 7,969
4 votes
Accepted

What are these two nerves running parallel to the spine called?

From this closeup image, you can see there is more than one nerve on each side that is parallel to the spine. Source: imgur.com First, they are the right and left sympathetic trunk that run from the ...
user avatar
  • 7,969
4 votes

Can catecholamines degrade back into tyrosine, or, is synthesis irreversible? (in human body)

A glance at the relevant BioCyc entry tells us that each reaction in the catecholamine biosynthesis pathway is irreversible. The standard free energy change of each reaction—again from BioCyc—is given ...
user avatar
  • 1,267
3 votes

What does sympathetic and parasympathetic 'tone' mean?

Short answer Parasympathetic tone is not necessarily mediated by tonic firing. Background Nice question! I think part of the confusion stems from terminology. Let's start with some definitions first. ...
user avatar
  • 51.2k
3 votes
Accepted

What is the difference between a dermatome and a sensory neurone?

This is just a confusion of English. "Supplied" is a bit of a weird term to use, I agree, due to the direction of information flow, but feel free to substitute in just "connected to&...
user avatar
  • 36.6k
3 votes
Accepted

what is meta-sympathetic nervous system?

The concept of a metasympathetic part of the autonomic nervous system (distinct from the sympathetic and parasympathetic parts) seems to be an idea discussed almost exclusively in the Russian ...
user avatar
  • 8,759
3 votes
Accepted

Salbutamol's Pathways of Interaction and Classification

An agonist works with the receptor: a substance that initiates a physiological response when combined with a receptor; in the case of salbutamol (or albutarol in the US) they activate the beta-2 ...
user avatar
3 votes
Accepted

What neuro-motor diseases cause the lower esophageal sphincter (LES) to malfunction?

This is called achalasia. According to UpToDate, the mechanism for this diseases are generally unknown. What is known, however, is that the esophagus has a neural system called the myenteric plexus ...
user avatar
3 votes

Is the autonomic nervous system only activated by internal stimuli?

Short answer External stimuli can drive autonomic responses. Background The autonomic nervous system is a visceral sensory and motor system. The viscera are the internal organs. Virtually all ...
user avatar
  • 51.2k
2 votes

Why does anxiety cause diarrhea or constipation?

Hraish is right about the relationship between emotions and gut-brain axis. Stress hormones released by the brain are responsible for the gut-brain reflexes. Anxiety is related to stress and stress ...
user avatar
  • 1,874
2 votes

Why do typical acetylcholinesterase inhibitors (like carbamates) have a greater parasympathetic effect than a sympathetic effect?

We were taught that ganglionic receptors have very high thresholds. So we need a very high concentration of the drug to produce the sympathetic effects. We even solved a hypothetical problem in class, ...
user avatar
  • 3,646
2 votes
Accepted

Voluntary actions of Autonomic Nervous System

I have no idea what the author has in mind, but their statement is wrong from the beginning: somatic motor activity is not always voluntary. Reflexes are a good and obvious example. "Fight or flight" ...
user avatar
  • 36.6k
2 votes
Accepted

Where are interneurons in Autonomic Nervous System?

It sort of depends on your definition of interneuron. Many school-level textbooks suggest that any neuron that has neurons both pre and post synaptically are interneurons. Therefore both the ...
user avatar
2 votes

Why should we preceed neostigmine by atropine in tubocurarine toxicity?

Tubocurarine is a non-depolarising neuromuscular blocking aqgent, that is, it acts as a competetive antagonist of Acetyl Choline at the Nicotinic receptors.(Toxicity/Effect: $-N$) Atropine is a ...
user avatar
  • 4,619
1 vote

Are "sympathetic nerves" the same as "cardiopulmonary splanchnic" nerves?

You might consider cross-posting to SE Medical sciences who know more about this stuff. I think that they are simply using a more general term than other authors. In the same way, most people call ...
user avatar
1 vote
Accepted

What does it mean to say that the sympathetic nervous system is organized for diffuse activity?

"Mobilize" in this context means to: to release (something stored in the organism) for bodily use Merriam-Webster "Diffuse" means "spread out": it doesn't say anything about whether the effect is ...
user avatar
  • 36.6k
1 vote

Can catecholamines degrade back into tyrosine, or, is synthesis irreversible? (in human body)

I do believe it's irreversible. When catecholamines have done their duty, they are degraded by COMT and MAO into products that are excreted in the urine. I'll make an example out drugs that are MAO ...
user avatar
  • 62
1 vote

Are the sympathetic and parasympathetic nervous systems exact opposites?

The Autonomic Nervous System is composed of the sympathetic and parasympathetic nervous systems. Each are dominant under different conditions - both are always active but one is dominant. An important ...
user avatar
  • 705
1 vote

Differentiation of norepinephrine and epinephrine in indications

The differences in the action/indication is because of differential affinity of the two molecules to different adrenergic receptors. The wikipedia page on Ardenergic receptor has a table which ...
user avatar
  • 35.1k

Only top scored, non community-wiki answers of a minimum length are eligible