Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Marijuana use affects blood flow in brain even after abstinence

08.02.2005


People who smoked marijuana had changes in the blood flow in their brains even after a month of not smoking, according to a study published in the February 8 issue of Neurology, the scientific journal of the American Academy of Neurology.


The findings could explain in part the problems with thinking or remembering found in other studies of marijuana users, according to study authors Ronald Herning, PhD, and Jean Lud Cadet, MD, of the National Institute on Drug Abuse in Baltimore, Md.

The study involved 54 marijuana users and 18 control subjects. The marijuana users volunteered to take part in a month-long inpatient program. The blood flow velocity in brain arteries was tested with transcranial Doppler sonography in all participants at the beginning of the study and again at the end of the month for the marijuana users.

The blood flow velocity was significantly higher in the marijuana users than in the control subjects, both at the beginning of the study and after a month of abstinence from marijuana use. The marijuana users also had higher values on the pulsatility index (PI), which measures the amount of resistance to blood flow. This is thought to be due to narrowing of the blood vessels that occurs when the circulation system’s ability to regulate itself is impaired.



"The marijuana users had PI values that were somewhat higher than those of people with chronic high blood pressure and diabetes," Herning said. "However, their values were lower than those of people with dementia. This suggests that marijuana use leads to abnormalities in the small blood vessels in the brain, because similar PI values have been seen in other diseases that affect the small blood vessels."

The PI values for light and moderate marijuana users improved over the month of abstinence. There was no improvement for heavy marijuana users. The light users smoked two to 15 joints per week. The moderate users smoked 17 to 70 joints per week, and the heavy users smoked 78 to 350 joints per week.

Marilee Reu | EurekAlert!
Further information:
http://www.aan.com

More articles from Studies and Analyses:

nachricht A sudden drop in outdoor temperature increases the risk of respiratory infections
11.01.2017 | University of Gothenburg

nachricht Urbanization to convert 300,000 km2 of prime croplands
27.12.2016 | Mercator Research Institute on Global Commons and Climate Change (MCC) gGmbH

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

A big nano boost for solar cells

18.01.2017 | Power and Electrical Engineering

Glass's off-kilter harmonies

18.01.2017 | Materials Sciences

Toward a 'smart' patch that automatically delivers insulin when needed

18.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>