Investigators Seek Facts on Marijuana

              Husband, Wife Team
Investigators Seek
Facts on Marijuana
By Margaret Martin
Times Medical Writer
In a laboratory at Louisiana State
University Medical School at Shreveport,
two scientists are putting marijuana
under the microscope of research trying
to find answers to a drug everybody
talks about but no one r e a l l y knows
about.
Dr. Joseph and Dr. Barbara Manno —
a husband and wife team — are both
assistant professors in pharmacology at
the medical school. Dr. Barbara is also
on the staff at tfhe Veterans Administra-tion
Hospital.
Both have Ph.D.s from the University
of Indiana Medical School. Her's is in
pharmcology, his is in toxicology.
In their office in the Medical School
Pharmacology Building on the hospital
grounds the two discussed their past,
present and future investigation into the
marijuana mystique.
"We are with marijuana today where
we were with alcohol 50 years ago" they
believe.
And like investigation on alcohol, the
research is being done backwards, the
clinical before the laboratory, they said.
They have done combined research
since 1967 with both rats and humans.
(Their work locally is strictly with rats,
Dr. Barbara wanted to emphasize.) They
make no moral judgments, give no
advice and are concerned with marijua-na
only as a drug.
The Mannos work as a team, yet have
separate research interests.
Dr. Joseph does point out that no one
can say marijuana is safe unless he
knows what kind of marijuana he is
smoking.
'No drug is safe," he added
explaining that different kinds of mari-juana
have varied degrees of potency.
(Dr. Barbara interjected a bit of humor,
They don't always get what they pay for
when they buy marijuana.") And they
said marijuana is a drug and acts like
other drugs.
The active ingredient in marijuana is
tetrahydrocannabinol, known as THC.
Put simply, what alcohol is to whiskey,
THC is to marijuana.
Hemp marijuana has a large stalk,
more fiber and a low concentration of
THC—1-lOth of 1 per cent. Smoking it
causes nothing more than a sore throat,"
said Dr. Joseph.
The drug type, grown in Mexico and
Southeast Asia, has from 1 per cent to 6
per cent THC content.
In their work with marijuana the
Mannos have taken a classical approach,
the same as that in any investigation of a
drug. We took a known sample of marijuana
with a known content of THC, to find out
what happens when m a r i j u a n a is
smoked, they explained.
They were among the first investiga-tors
to establish a dosage from a
cigarette and produce an effect, some-thing
s u s p e c t e d , but not confirmed
previously.
Student Volunteers
Using medical student volunteers at
Indiana — some of whom said they had
smoked marijuana before — the Mannos
showed that the more THC inhaled in a
marijuana cigarette, the more inhibiting
effects of the THC on the person's
performance of psychomotor functions.
Using a battery of complicated tests,
the researchers came up with some
simple answers about marijuana.
Marijuana does, Indeed, inhibit per-formance
as indicated by tests before
and after smoking marijuana with a
signal pursuit meter. (The students were
given four different dosages of marijua-na,
depending on their weight, dosages
which had been worked out scientifically
by Dr. Joseph. Subsequently the same
test was used by other investigators who
injected THC intravenously, and got
similar effects. Volunteers using alcohol
for tests purposes were given one drink
of about three ounces of 80 proof whisky.)
While alcohol itself produced detri-mental
effects on the performance,
marijuana produced even greater inhibi-tions
and alcohol and marijuana pro-duced
effects much greater than mari-juana
or alcohol alone, Dr. Joseph said.
Marijuana, they found, speeds up the
heart rate.
It causes reddening of the eyes,
meaning dialating blood vessels some-where
in the body.
Balancing tests showed marijuana
affects the equilibrium.
"As they smoked marijuana contain-ing
different concentrations of THC,
there were different effects," he said.
He explained that all marijuana is
different, and "when you talk about
marijuana, you are talking about the
THC content."
Was the increased heart rate caused
by excitement, anticipation of smoking
marijuana — much like some people get
a "high" on a taste of alcohol?
Did the smoke of the cigarette bring
on the redding of the eyes?
Tests showed that the i n c r e a s e d
beating of the heart, the change of eye
color, came about at different times,
dependent on the amount of drug dosage.
Other investigators, injecting pure THC
intravenously, have also produced an
increase in the heart beat, Dr. Joseph
said.
Complain of Cold Hands
Marijuana smokers also complain of
cold hands "and very little has been
done to investigate this," Dr. Joseph
said, "but we suspect it is caused by
constrictions of the blood vessels some-where."
To conduct isolated heart experi-ments,
Dr. Barbara took the hearts from
rats, put them in an artificial environ-ment
and maintained body temperature
and kept a salt solution pumping through
them. They remained viable for up to six
hours.
Applying THC to the hearts, the
scientist found that the vascular system
constricts, meaning the vessels tighten
up.
She found that the force of the heart
beat — though not the heart beat itself —
d r o p p e d , "never to return to the
condition before the drug was injected."
Her experiments now are dealing with
whether the change in the cardiovascular
system is due to direct effec of the drug
on the heart or if the action is controlled
by the brain.
The body has a system of checks and
balances, the two explained, "and we are
attempting to see which part is out of
balance."
Their two phases of c o n t i n u i n g
research — which is being done on a
$10,000 renewable National Institutes of
Health Grant — deals with the intact rat
and the isolated heart.
One of the q u e s t i o n s they are
attempting to answer deals with the
biochemical pharmacology changes in
the body tissues brought about by
exposure to THC. Are there biochemical
changes brought about by THC and do
they alter the biochemical functions of
the tissues.
In "Turned on by God," J. Elliott
Corbett quotes, "In no area of public
controversy are falsehoods as mixed
with facts as they are with respect to
marijuana."
In small unheralded laboratories of
the world, people like the Mannos are
using the weight of science to replace the
myths about marijuana with the facts.
(Times Photo by Billy Upshaw)
Toxicologist Dr. Joseph Manno
. . . working with the intact rat