Reuseable frogs. Free frogspawn forever!

[fightingthecage]

I find this disturbing, I don't know why. It's on the subject of pregnancy testing.

Selmar Aschheim and Bernhard Zondek introduced testing based on the presence of hCG in 1928. In their test an infantile female mouse was injected subcutaneously with urine of the person to be tested, and some time later the mouse was killed and dissected. Presence of ovulation indicated that the urine contained hCG and meant that the person was pregnant. A similar test was developed using immature rabbits, the rabbit test. Here, too, it was necessary to kill the animal to check its ovaries. An improvement arrived with the frog test that was still used in the 1950s. A female frog was injected with serum or urine of the patient. If the frog produced eggs within the next 24 hours, the test was positive. In the frog test, the animal remained alive, and could be used again.

So, the chemical from the human forced an animal to ovulate? That's just...gross. Although I am cracking up at the idea of reuseable frogs, even if it does seem absolutely unbelievable that it was still a method used into the 1950s.

Grossness aside (incidentally, I also find it very cruel that the animals were randomly dissected. Wouldn't it have been more humane to just wait and see if you were up the duff?), I still don't understand. Why does a chemical from a human force ovulation in an animal? Especially weird that it works on amphibians - I suppose other mammals make a little bit of sense at least. Enlighten me, science people?

Edit: One other thing. If the mice were injected and then killed some time later...well, don't female mice ovulate anyway? I don't know. Don't most mammals? So how did they know that ovulation was prompted by the injection of human urine? Or am I displaying my extrodinary biological stupidity here?

Comments

[ashen_key]

So how did they know that ovulation was prompted by the injection of human urine?

Possibly, this is just me being incredibly dopey due to illness + drugs + lack of sleep, but I'm drawing a blank on that as well.

[fightingthecage.livejournal.com]

We need a scientist. Totally because I am too lazy to trawl through the internets to find an answer.

[ashen_key]

Well, I imagine that they'd have to have known the cycle of the mice in question, and made sure (and they would be able to check, somehow, because humans are the only ones who hide their ovulation) and did injecty thing when they weren't, but the some time later makes me blink, because they are MICE. And mice are super-quick on the whole cycle thing and bah.

Still.

The reusable frogs thing made me giggle. Somewhat morbidly, I admit.

[fightingthecage.livejournal.com]

They have quick cycles? Well, that makes the test even more crap. Maybe it didn't work and they were just trying to see if it did - p'raps the frog thingy was more successful because they checked within 24 hours.

The whole thing still makes me squick. It almost feels like bestiality.

[ashen_key]

Well, I imagine that they would, because look at the way mice can breed. You get plagues in no time and millions of mice running wild (or, possibly that's just an Australian thing due to lack of mice predators. anyway).

I'm just...too doped up to do more then giggle, actually. And scientists do horrible things to animals, so I'm not even surprised.

[topaz-eyes.livejournal.com]

Many (if not most) proteins in humans are very similar to those in other animals, so they will act in a similar way when injected into another animal. hCG (human chorionic gonadotropin) is a protein hormone. Mice and rabbits and frogs have their own species-specific CG hormones, but the hCG is similar enough to the mouse or rabbit or frog hormone, that it will trigger ovulation.

My guess as to the reusability of frogs, is that frogs expel their eggs (since fertilization happens outside the body) so it's very easy to detect whether ovulation occurred. Mice and rabbits are mammals, therefore, their eggs are released inside their bodies. Infantile mice or rabbits were used because they haven't reached sexual maturity. Once a mouse or rabbit is sexually mature, they have their own estrus/ovulation cycles, so the infantile animals could be used only once.

Makes one appreciate the current pregnancy testing methods, don't it? *g*

[fightingthecage.livejournal.com]

Aha! That makes a lot more sense, thank you. You should be the one writing Wikipedia articles on this subject, obviously. It still grosses me out though. Even more so since I asked my mother about it last night and she couldn't see why I thought it was weird that it was used into the 50s. Apparantly it was both common knowledge and normal back then, even though no one talked about such things. So. Weird.

But thanks for clearing that up, it was doing my head in.

[shellebelle93.livejournal.com]

Let us all bow our heads and thank God for the inventor of the 'stick test'.

[fightingthecage.livejournal.com]

Amen to that!.