 |
 |
Barb_MSN asked: > ... the heart is a muscle .... Does anyone KNOW if the heart CAN be > affected by PD? Very interesting question -- if PD affects movement, what about heart muscle contractions? I got curious and did a little research. Here's some of what I found. Any additions or corrections to the following will be appreciated. Thankfully, the heart does not experience any of the principal Parkinsonian motor effects -- tremor, bradykinesia, and stiffness -- nor the drug effect dyskinesia. If it did, we would certainly know about it! This is because the heart's basic activating and control mechanism is within the heart itself, and not in the motor centers of the brain. Electrical impulses originating within the upper right chamber of the heart in specialized muscle tissue called the sinoatrial node (S-A node) set the basic heartbeat and cause contactions in those parts of the heart that contract. This gives the heart a fair degree of independence and isolation from injury elsewhere in the body. Pretty good design, I'd say. Hormones such as epinephrine and signals via nerves connected to the autonomic nervous system modify the basic heartbeat, according to, e.g., the body's needs for more or less oxygen. It's via the autonomic nervous system that effects on blood pressure and heartbeat related to PD occur. This is more the area under discussion, and here I need to do a lot more research. To be continued (if and when I am able). Phil Tompkins Hoboken NJ age 61/dx 1990